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Sample records for nerve root displacement

  1. Prevention of nerve root adhesions after laminectomy.

    PubMed

    Yong-Hing, K; Reilly, J; de Korompay, V; Kirkaldy-Willis, W H

    1980-01-01

    In repeat lumbar surgery for failure of the original operation to provide lasting relief, well-organized fibrous tissue is often noted binding together the dura, nerve roots, and erector spinae muscles. Lumbar laminectomy was carried out in 46 dogs and seven groups of animals studied. Gelfoam failed to prevent fibrosis. Free fat grafts prevented fibrosis whether the graft was placed at the laminectomy site or around the nerve roots. Vascularization of the grafts was demonstrated by injection of India ink before sacrifice. Ligamentum nuchae, which is similar to ligamentum flavum in its high elastic content, was also effective in preventing scar formation. The operative biopsy findings at reexploration in four patients who had free fat grafts following laminectomy are presented. PMID:7361199

  2. Safety of CT-Guided Lumbar Nerve Root Infiltrations

    PubMed Central

    Gossner, Johannes

    2014-01-01

    Summary Selective nerve root infiltrations are frequently performed in patients with lumbar radiculopathy. Computed tomography (CT) is now commonly used for image guidance. Despite the widespread use of CT-guided lumbar nerve root infiltrations few studies have systematically examined the safety of this approach. In a two-year period, 231 lumbar nerve root infiltrations were performed on in-patients and were retrospectively reviewed. No major complications like inflammation (especially spondylodiscitis), large haematomas requiring surgery, severe allergic reactions or spinal ischaemia occurred. In accordance with other published studies, CT-guided lumbar nerve root infiltrations seem to be safe. To minimize the risk of catastrophic neurological complications due to spinal ischaemia, careful needle placement dorsal to the nerve root and the use of a non-particulate corticosteroid, like dexamethasone, are advocated. PMID:25363255

  3. Conjoint Lumbosacral Nerve Root-A Case Report

    PubMed Central

    Jokhi, Vispi.H.; Ponde, Saurabh Vilas; Sonawane, Chandrashekhar; Bansal, Samarjit Singh; Chavhan, Ashwin

    2015-01-01

    Introduction: Conjoint nerve root is embryological nerve root anomaly mainly involving lumbosacral region. The anomalous roots present primarily as a bifid, conjoined structure arising from a wide area of the dura. Because of their size and attachment to surrounding structures, they are uniquely susceptible to trauma. The effects of compression and entrapment are amplified in the presence of stenosis of the lateral recesses where developmental changes and disc herniations deplete the available reserve space [1]. Case Report: We report a case of conjoint lumbosacral nerve root which was missed on MRI and diagnosed intra-operatively. Conclusion: The importance of the case report lies in the fact that one must be aware of finding conjoint nerve root directly while operating and do appropriate level of surgery, misinterpretation can lead to devastating results. PMID:27299088

  4. Study on lumbosacral nerve root compression using DTI

    PubMed Central

    Li, Jinfeng; Wang, Yonghao; Wang, Yueyi; Lv, Yang; Ma, Lin

    2016-01-01

    Diffusion tensor imaging (DTI) can objectively describe the distribution of nerve roots in morphology, and provide a set of objective reference data on the quantitative indicators. The present study aimed to investigate the value of DTI in lumbosacral nerve root compression in patients with lumbar intervertebral disc degeneration. DTI was performed in 45 patients with lumbar intervertebral disc degeneration. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values were measured in compressed and normal nerve roots. Fiber tracking imaging was also applied to observe the lumbosacral nerve roots. ADC value was significantly lower in the compressed group (1.314±0.14 mm2/sec) compared to in the uncompressed group (1.794±0.11 mm2/sec) (P<0.05). The FA value was significantly lower in the compressed group (0.196±0.020) compared to the uncompressed group (0.272±0.016) (P<0.05). DTI can evidently reveal the compressed nerve roots. DTI could be used to evaluate the lumbosacral nerve injury in patients with lumbar intervertebral disc degeneration to quantitatively assess nerve roots. PMID:27602215

  5. [Prevention from secondary nerve root adhesion: an experimental study].

    PubMed

    Yao, M; Sun, Y; Yan, J

    1996-06-01

    In the study, 27 dogs were divided into three groups: A, B and C. Then all of the dogs had their lumbar intervertebral disks removed. Into the wounded cavity of group A, 1 ml of dimethicone was dropped and gelatin sponge was applied on the surface of the nerve root of group B. Group C was served as the control. The dogs were killed and the operation area was removed respectively 2 weeks, 4 weeks, and 12 weeks after the operation for macroscopical observation, nerve root motility measurement and histological examination. The result of the experiment proved that dimethicone was fairly effective in the prevention from secondary nerve root adhesion. While gelatin sponge in the process of its absorption induced the formation of quite a few scar tissues, thus aggrevating nerve root adhesion. PMID:9594172

  6. [Sacral nerve root cysts. Discussion on the mechanism of nerve root suffering. Apropos of 4 cases].

    PubMed

    Bourgeois, P; Gaillard, S; Chastanet, P; Christiaens, J L

    1997-01-01

    Low back pain, sciatia or perineal chronic pain are sometimes related to perineural sacral cysts. Surgical treatment is difficult and may lead to pain or neurological worsening. We report four cases of symptomatic perineural cysts; three of them where operated on with two good results and one increasing perineal pain. Anatomical and radiological description are reviewed. From a therapeutical point of view, we can distinguish two clinical types of radicular suffering. Perineural cyst can cause a commun radicular extrinsic compression; in such a case surgical operation will improve radicular pain. The cystic nerve root can present an intrinsic suffering because of on intradural dilaceration. Then surgery must be avoided specially when many roots are involved because it may worsen the pluriradicular suffering. PMID:9686226

  7. Morphometric data of canine sacral nerve roots with reference to electrical sacral root stimulation.

    PubMed

    Rijkhoff, N J; Koldewijn, E L; d'Hollosy, W; Debruyne, F M; Wijkstra, H

    1996-01-01

    Experiments to investigate restoration of lower urinary tract control by electrical stimulation of the sacral nerve roots are mostly performed on dogs, yet little morphometric data (such as canine root and fiber diameter distributions) are available. The aim of this study was to acquire morphometric data of the intradural canine sacral dorsal and ventral roots (S1-S3). Cross-sections of sacral roots of two beagle dogs were analyzed using a light microscope and image processing software. The cross-sectional area of each root was measured. The diameters of the fibers and the axons in the cross-sections of the S2 and S3 roots were measured and used to construct nerve fiber diameter frequency distribution histograms. The results show a unimodal diameter distribution for the dorsal roots and a bimodal distribution for the ventral roots. In addition the average ratio g of the axon diameter to fiber diameter was calculated for each root. PMID:8732990

  8. Metastatic nerve root tumor: A case report and literature review

    PubMed Central

    LI, LONG; WU, YUAN; HU, LIU; XU, HONGBIN; HE, HAICUI; HU, DESHENG

    2016-01-01

    Nerve root metastasis of cancer has been rarely reported. We herein report the case of a cervical cancer patient with metastasis to peripheral nerve roots. A 47 year-old woman with cervical squamous cell carcinoma was admitted to our department with a 6-month history of right leg pain, and was investigated for cancer recurrence. Magnetic resonance imaging revealed lymph node metastasis near the right iliac blood vessels; the patient was then treated with chemotherapy with paclitaxel and carboplatin. However, the pain worsened and the muscle strength of her right leg decreased. On positron emission tomography/computed tomography scans, the sacral plexus L5/S1 and L4/5 nerves appeared thickened, suggesting nerve metastases. Intensity-modulated radiation therapy was applied, with notable clinical benefit. However, the patient succumbed to the disease 3 months later. PMID:27284440

  9. Proposed Classification of Auriculotemporal Nerve, Based on the Root System

    PubMed Central

    Komarnitki, Iulian; Tomczyk, Jacek; Ciszek, Bogdan; Zalewska, Marta

    2015-01-01

    The topography of the auriculotemporal nerve (ATN) root system is the main criterion of this nerve classification. Previous publications indicate that ATN may have between one and five roots. Most common is a one- or two-root variant of the nerve structure. The problem of many publications is the inconsistency of nomenclature which concerns the terms “roots”, “connecting branches”, or “branches” that are used to identify the same structures. This study was performed on 80 specimens (40 adults and 40 fetuses) to propose a classification based on: (i) the number of roots, (ii) way of root division, and (iii) configuration of interradicular fibers that form the ATN trunk. This new classification is a remedy for inconsistency of nomenclature of ATN in the infratemporal fossa. This classification system has proven beneficial when organizing all ATN variants described in previous studies and could become a helpful tool for surgeons and dentists. Examination of ATN from the infratemporal fossa of fetuses (the youngest was at 18 weeks gestational age) showed that, at that stage, the nerve is fully developed. PMID:25856464

  10. Spontaneous lateral pontine hemorrhage with associated trigeminal nerve root hematoma.

    PubMed

    Veerapen, R

    1989-09-01

    Spontaneous hemorrhage into the lateral part of the pons with sequelae compatible with survival has been documented previously. The author describes an unusual case with spontaneous hemorrhage into the lateral pons, with intraneural extension into the right trigeminal nerve root. Radiological features were of an expanding mass of the cerebellopontine angle. The patient was treated surgically with success. PMID:2771016

  11. The diameters and number of nerve fibers in spinal nerve roots

    PubMed Central

    Liu, YongTao; Zhou, XiaoJi; Ma, Jun; Ge, YingBin; Cao, Xiaojian

    2015-01-01

    Objective To investigate the anatomical and histological features of spinal nerve roots and provide base data for neuroanastomosis therapy for paraplegia. Methods Spinal nerve roots from C1 to S5 were exposed on six adult cadavers. The diameter and the number of nerve fibers of each nerve root were measured, respectively, with a caliper and image analysis software. Results As for ventral roots, the diameter of C5 (2.50 ± 0.55 mm) was the largest in cervical segments. In thoracic and lumbosacral segments, the diameter gradually increased from T11 to S1 and then decreased from S1 to S5 except L3. S1 (1.43 ± 0.16 mm) was the thickest root and S5 (0.14 ± 0.02 mm) was the thinnest one. As for dorsal roots, the diameter of C7 (4.61 ± 0.87 mm) was the largest in cervical segments. From T11 to S1, the diameter increased and then decreased gradually from S1 to S5. The diameter of dorsal roots from T1 to S5 was largest at S1 (2.95 ± 0.57 mm) and smallest at S5 (0.27 ± 0.13 mm), respectively. C7 (8467 ± 1019), T12 (6538 ± 892), L3 (9169 ± 1160), and S1 (8253 ± 1419) ventral roots contained the most nerve fibers in cervical, thoracic, lumbar, and sacral segments, respectively. Similarly, C7 (39 653 ± 8458), T1 (26 507 ± 7617), L5 (34 455 ± 2740), and S1 (41 543 ± 3036) dorsal roots, respectively, contained the most nerve fibers in their corresponding segments. Conclusion The findings in the current study provided the imperative data and may be valuable for spinal nerve root microanastomosis surgery in the paraplegic patients. PMID:24605949

  12. [Nerve root compression by gas containing lumbar disc herniation--case report].

    PubMed

    Yasuoka, Hiroki; Nemoto, Osamu; Kawaguchi, Masahisa; Naitou, Satoko; Yamamoto, Kouji; Ukegawa, You

    2009-06-01

    The radiographic appearance of gas collection in the intervertebral disc represents the so-called "vacuum phenomenon." Incidence of the vacuum phenomenon on plain radiographs is reported to be 1-20%, whereas gas-containing disc herniations are rarely observed. We present a case report involving a patient with L4/5 gas-containing disc herniation, which was demonstrated by CT and MRI scans and was also surgically documented. A 48-year-old man with no previous back trauma presented with a 14-day history of left leg pain. On neurologic examination, the straight leg raising test was positive at 60degrees. Leg muscle strength was weak on the extensor hallucis longus. Sensory disturbances and abnormalities in deep-tendon reflexes were not observed. Lumbar roentogenograms showed "vacuum phenomenon" at L2/3, L4/5 and the L5/S disc space. MRI indicated a herniated disc at L4/5 displacing the dural sac and a focal low intensity in the lesion. Administration of an epidural block relieved the patient's symptoms. Ten months later, the patient reported a gradual return of similar left leg pain. His symptoms did not respond to conservative management. Lumbar spine films indicated abnormalities identical to the original results. MRI showed an enlarged area of low intensity with compression of the left L5 nerve root. In addition to recurrent pain, discography with metrizamide injections confirmed the presence of intradiscal gas and compression of the left L5 nerve root. During surgery, a gray-bluish air mass compressing the L5 nerve root was identified. Manipulation of the mass resulted in rupture and the release of gas. The displaced nerve root immediately relaxed to its normal position. Seven months after the operation, the patient remains free of pain. PMID:19526837

  13. Characterization of a chondroitin sulfate hydrogel for nerve root regeneration

    NASA Astrophysics Data System (ADS)

    Conovaloff, Aaron; Panitch, Alyssa

    2011-10-01

    Brachial plexus injury is a serious medical problem that affects many patients annually, with most cases involving damage to the nerve roots. Therefore, a chondroitin sulfate hydrogel was designed to both serve as a scaffold for regenerating root neurons and deliver neurotrophic signals. Capillary electrophoresis showed that chondroitin sulfate has a dissociation constant in the micromolar range with several common neurotrophins, and this was determined to be approximately tenfold stronger than with heparin. It was also revealed that nerve growth factor exhibits a slightly stronger affinity for hyaluronic acid than for chondroitin sulfate. However, E8 chick dorsal root ganglia cultured in the presence of nerve growth factor revealed that ganglia cultured in chondroitin sulfate scaffolds showed more robust growth than those cultured in control gels of hyaluronic acid. It is hypothesized that, despite the stronger affinity of nerve growth factor for hyaluronic acid, chondroitin sulfate serves as a better scaffold for neurite outgrowth, possibly due to inhibition of growth by hyaluronic acid chains.

  14. Characterization of a chondroitin sulfate hydrogel for nerve root regeneration.

    PubMed

    Conovaloff, Aaron; Panitch, Alyssa

    2011-10-01

    Brachial plexus injury is a serious medical problem that affects many patients annually, with most cases involving damage to the nerve roots. Therefore, a chondroitin sulfate hydrogel was designed to both serve as a scaffold for regenerating root neurons and deliver neurotrophic signals. Capillary electrophoresis showed that chondroitin sulfate has a dissociation constant in the micromolar range with several common neurotrophins, and this was determined to be approximately tenfold stronger than with heparin. It was also revealed that nerve growth factor exhibits a slightly stronger affinity for hyaluronic acid than for chondroitin sulfate. However, E8 chick dorsal root ganglia cultured in the presence of nerve growth factor revealed that ganglia cultured in chondroitin sulfate scaffolds showed more robust growth than those cultured in control gels of hyaluronic acid. It is hypothesized that, despite the stronger affinity of nerve growth factor for hyaluronic acid, chondroitin sulfate serves as a better scaffold for neurite outgrowth, possibly due to inhibition of growth by hyaluronic acid chains. PMID:21804177

  15. Intra-radicuar Disc Herniation mimicking a Nerve Root Tumor

    PubMed Central

    Pillai, Suresh Sivadasan

    2012-01-01

    Introduction: Intra-radicular disc herniations are rare disorders with only few cases reported in literature. In most of these cases there is evidence of some part of the disc in adjacent area. We present a case of completely intra-radicular disc which was misdiagnosed as nerve root tumor as there was no evidence of disc prolapse at the time of diagnosis. Case Presentation: 51 year old male presented with history of severe back pain radiating to right lower limb since 11/2 month. MRI showed hypointense lesion completely inside the S1 root and a provisional diagnosis of nerve root tumor was done. At surgery, fluffy material was removed from the lesion which was histopathologically confirmed as intervertebral disc. Post operatively all symptoms of patient was relieved except dysesthesia in sole which lasted for a year post surgery. At 5 year follow up patient has no symptoms. Conclusion: A diagnosis of intra-radicular disc should be considered in differential of nerve root tumor. Surgical excision of intra-radicular disc gives good clinical and functional results.

  16. Infrared neural stimulation of human spinal nerve roots in vivo

    PubMed Central

    Cayce, Jonathan M.; Wells, Jonathon D.; Malphrus, Jonathan D.; Kao, Chris; Thomsen, Sharon; Tulipan, Noel B.; Konrad, Peter E.; Jansen, E. Duco; Mahadevan-Jansen, Anita

    2015-01-01

    Abstract. Infrared neural stimulation (INS) is a neurostimulation modality that uses pulsed infrared light to evoke artifact-free, spatially precise neural activity with a noncontact interface; however, the technique has not been demonstrated in humans. The objective of this study is to demonstrate the safety and efficacy of INS in humans in vivo. The feasibility of INS in humans was assessed in patients (n=7) undergoing selective dorsal root rhizotomy, where hyperactive dorsal roots, identified for transection, were stimulated in vivo with INS on two to three sites per nerve with electromyogram recordings acquired throughout the stimulation. The stimulated dorsal root was removed and histology was performed to determine thermal damage thresholds of INS. Threshold activation of human dorsal rootlets occurred in 63% of nerves for radiant exposures between 0.53 and 1.23  J/cm2. In all cases, only one or two monitored muscle groups were activated from INS stimulation of a hyperactive spinal root identified by electrical stimulation. Thermal damage was first noted at 1.09  J/cm2 and a 2∶1 safety ratio was identified. These findings demonstrate the success of INS as a fresh approach for activating human nerves in vivo and providing the necessary safety data needed to pursue clinically driven therapeutic and diagnostic applications of INS in humans. PMID:26157986

  17. Familial risks for nerve, nerve root and plexus disorders in siblings based on hospitalisations in Sweden

    PubMed Central

    Hemminki, Kari; Li, Xinjun; Sundquist, Kristina

    2007-01-01

    Background Nerve, nerve root and plexus disorders are common diseases, but little is known about familial clustering in these diseases. This is, to our knowledge, the first systematic family study carried out on these diseases. Methods Familial risks for siblings who were hospitalised for nerve, nerve root and plexus disorders in Sweden were defined. A nationwide database for neurological diseases was constructed by linking the Multigeneration Register on 0–69‐year‐old siblings to the Hospital Discharge Register covering the years 1987–2001. Standardised risk ratios (SIRs) were calculated for affected sibling pairs by comparing them with those whose siblings had no neurological disease. Results 29 686 patients, 43% men and 57% women, were diagnosed at a mean age of 37.5 years. 191 siblings were hospitalised for these disorders, giving an overall SIR of 2.59 (95% CI 1.58 to 4.22), with no sex difference. Plantar nerve mononeuritis and carpal tunnel syndrome showed the highest familial risks: 4.82 (1.08 to 16.04) and 4.08 (2.07 to 7.84), respectively. Lateral poplitean and plantar nerve neuritis preferentially affected women, with SIRs of >8; disorders of the other cranial nerves affected only men, with an SIR of >10. Concordant trigeminal neuralgia, Bell's palsy and carpal tunnel syndrome showed familial risks, but, with the exception of Bell's palsy, they also showed correlation between spouses, implying environmental sharing of risk factors. Conclusions The results cannot distinguish between inheritable or shared environmental factors, or their interactions, but they clearly show familial clustering, suggestive of multifactorial aetiology and inviting for aetiological research. PMID:17183020

  18. Spinal Nerve Root Enhancement on MRI Scans in Children: A Review.

    PubMed

    Kontzialis, Marinos; Poretti, Andrea; Michell, Hans; Bosemani, Thangamadhan; Tekes, Aylin; Huisman, Thierry A G M

    2016-01-01

    Spinal nerve root enhancement in pediatric patients is generally nonspecific, and clinical and laboratory correlation is essential. Nerve root enhancement indicates lack of integrity of the blood-nerve barrier. In this review, we will present a range of pediatric conditions that can present with spinal nerve root enhancement including inflammatory, infectious, hereditary, and neoplastic causes. Familiarity with the various pathologic entities associated with spinal nerve root enhancement is important for a concise differential diagnosis in the appropriate clinical setting. This will avoid unnecessary additional investigations. PMID:26365273

  19. [Repositioning injuries of nerve root L5 after surgical treatment of high degree spondylolistheses and spondyloptosis--in vitro studies].

    PubMed

    Albrecht, S; Kleihues, H; Gill, C; Reinhardt, A; Noack, W

    1998-01-01

    Temporary or persistent paralysis of the fifth lumbar nerve root have been frequently reported as complications following reposition of high degree spondylolisthesis. According to an outcome analysis of sixty-four patients, we found an increased incidence of motor damages after reduction of Meyerding degree four anterolisthesis or spondyloptosis. There were no signs of intradural root compression or nerve injury tracable. In order to detect extraforaminal strictures, the anatomic course of the lumbosacral plexus and its relation to neighbouring structures, especially pelvivertebral connective tissue junctions were recorded in cadavric measurements. Beside an number of variations in origin and course of the iliolumbar ligament complex, we observed a junction between os sacrum and the anterior part of the fifth lumbar vertebrae in 14/30 specimen, constantly running anterior to the fifth lumbar nerve root. In addition the nerve was fixed to the sacral periostium a few centimeters distal this crossing in about 20% of all cases. Pathophysiological effects were measured in reposition trials, using a continuous pressure monitoring system. A reposition of more than 20 mm resulted in a perineural pressure > 30 mmHg. This caused a nerve fiber deformation at the edge of the compressed nerve segment. Increased pressure leads to a nodular displacement of perineural fat as well as intraneural fascicles. PMID:9615983

  20. Chronic sciatic nerve compression induces fibrosis in dorsal root ganglia

    PubMed Central

    LI, QINWEN; CHEN, JIANGHAI; CHEN, YANHUA; CONG, XIAOBIN; CHEN, ZHENBING

    2016-01-01

    In the present study, pathological alterations in neurons of the dorsal root ganglia (DRG) were investigated in a rat model of chronic sciatic nerve compression. The rat model of chronic sciatic nerve compression was established by placing a 1 cm Silastic tube around the right sciatic nerve. Histological examination was performed via Masson's trichrome staining. DRG injury was assessed using Fluoro Ruby (FR) or Fluoro Gold (FG). The expression levels of target genes were examined using reverse transcription-quantitative polymerase chain reaction, western blot and immunohistochemical analyses. At 3 weeks post-compression, collagen fiber accumulation was observed in the ipsilateral area and, at 8 weeks, excessive collagen formation with muscle atrophy was observed. The collagen volume fraction gradually and significantly increased following sciatic nerve compression. In the model rats, the numbers of FR-labeled DRG neurons were significantly higher, relative to the sham-operated group, however, the numbers of FG-labeled neurons were similar. In the ipsilateral DRG neurons of the model group, the levels of transforming growth factor-β1 (TGF-β1) and connective tissue growth factor (CTGF) were elevated and, surrounding the neurons, the levels of collagen type I were increased, compared with those in the contralateral DRG. In the ipsilateral DRG, chronic nerve compression was associated with significantly higher levels of phosphorylated (p)-extracellular signal-regulated kinase 1/2, and significantly lower levels of p-c-Jun N-terminal kinase and p-p38, compared with those in the contralateral DRGs. Chronic sciatic nerve compression likely induced DRG pathology by upregulating the expression levels of TGF-β1, CTGF and collagen type I, with involvement of the mitogen-activated protein kinase signaling pathway. PMID:26820076

  1. Chronic sciatic nerve compression induces fibrosis in dorsal root ganglia.

    PubMed

    Li, Qinwen; Chen, Jianghai; Chen, Yanhua; Cong, Xiaobin; Chen, Zhenbing

    2016-03-01

    In the present study, pathological alterations in neurons of the dorsal root ganglia (DRG) were investigated in a rat model of chronic sciatic nerve compression. The rat model of chronic sciatic nerve compression was established by placing a 1 cm Silastic tube around the right sciatic nerve. Histological examination was performed via Masson's trichrome staining. DRG injury was assessed using Fluoro Ruby (FR) or Fluoro Gold (FG). The expression levels of target genes were examined using reverse transcription‑quantitative polymerase chain reaction, western blot and immunohistochemical analyses. At 3 weeks post‑compression, collagen fiber accumulation was observed in the ipsilateral area and, at 8 weeks, excessive collagen formation with muscle atrophy was observed. The collagen volume fraction gradually and significantly increased following sciatic nerve compression. In the model rats, the numbers of FR‑labeled DRG neurons were significantly higher, relative to the sham‑operated group, however, the numbers of FG‑labeled neurons were similar. In the ipsilateral DRG neurons of the model group, the levels of transforming growth factor‑β1 (TGF‑β1) and connective tissue growth factor (CTGF) were elevated and, surrounding the neurons, the levels of collagen type I were increased, compared with those in the contralateral DRG. In the ipsilateral DRG, chronic nerve compression was associated with significantly higher levels of phosphorylated (p)‑extracellular signal‑regulated kinase 1/2, and significantly lower levels of p‑c‑Jun N‑terminal kinase and p‑p38, compared with those in the contralateral DRGs. Chronic sciatic nerve compression likely induced DRG pathology by upregulating the expression levels of TGF‑β1, CTGF and collagen type I, with involvement of the mitogen‑activated protein kinase signaling pathway. PMID:26820076

  2. Clinical applications of diffusion magnetic resonance imaging of the lumbar foraminal nerve root entrapment

    PubMed Central

    Ohtori, Seiji; Yamashita, Masaomi; Yamauchi, Kazuyo; Suzuki, Munetaka; Orita, Sumihisa; Kamoda, Hiroto; Arai, Gen; Ishikawa, Tetsuhiro; Miyagi, Masayuki; Ochiai, Nobuyasu; Kishida, Shunji; Masuda, Yoshitada; Ochi, Shigehiro; Kikawa, Takashi; Takaso, Masashi; Aoki, Yasuchika; Toyone, Tomoaki; Suzuki, Takane; Takahashi, Kazuhisa

    2010-01-01

    Diffusion-weighted imaging (DWI) can provide valuable structural information about tissues that may be useful for clinical applications in evaluating lumbar foraminal nerve root entrapment. Our purpose was to visualize the lumbar nerve root and to analyze its morphology, and to measure its apparent diffusion coefficient (ADC) in healthy volunteers and patients with lumbar foraminal stenosis using 1.5-T magnetic resonance imaging. Fourteen patients with lumbar foraminal stenosis and 14 healthy volunteers were studied. Regions of interest were placed at the fourth and fifth lumbar root at dorsal root ganglia and distal spinal nerves (at L4 and L5) and the first sacral root and distal spinal nerve (S1) on DWI to quantify mean ADC values. The anatomic parameters of the spinal nerve roots can also be determined by neurography. In patients, mean ADC values were significantly higher in entrapped roots and distal spinal nerve than in intact ones. Neurography also showed abnormalities such as nerve indentation, swelling and running transversely in their course through the foramen. In all patients, leg pain was ameliorated after selective decompression (n = 9) or nerve block (n = 5). We demonstrated the first use of DWI and neurography of human lumbar nerves to visualize and quantitatively evaluate lumbar nerve entrapment with foraminal stenosis. We believe that DWI is a potential tool for diagnosis of lumbar nerve entrapment. PMID:20632042

  3. Secondary chronic cluster headache due to trigeminal nerve root compression.

    PubMed

    Mjåset, Christer; Russell, M B; Russell, M Bjørn

    2010-12-01

    A 50-year-old woman had a gradual onset of chronic headache located in the right temporal region and a burning sensation in the root of the tongue which over a year evolved into chronic cluster headache with a milder chronic headache in-between the severe cluster headache attacks. A cerebral magnetic resonance imaging (MRI) showed vascular compression of the trigeminal nerve root on the pain side. Neurosurgery microvascular decompression relieved the patient's chronic cluster headache, the chronic intermittent headache and the burning tongue sensation. The effect was persistent at a 1 year follow-up. Patients with atypical symptoms of cluster headache should be examined with cerebral MRI angiography of arteries and veins to exclude symptomatic causes. PMID:20384588

  4. Median nerve deformation and displacement in the carpal tunnel during index finger and thumb motion.

    PubMed

    van Doesburg, Margriet H M; Yoshii, Yuichi; Villarraga, Hector R; Henderson, Jacqueline; Cha, Stephen S; An, Kai-Nan; Amadio, Peter C

    2010-10-01

    The purpose of this study was to investigate the deformation and displacement of the normal median nerve in the carpal tunnel during index finger and thumb motion, using ultrasound. Thirty wrists from 15 asymptomatic volunteers were evaluated. Cross-sectional images during motion from full extension to flexion of the index finger and thumb were recorded. On the initial and final frames, the median nerve, flexor pollicis longus (FPL), and index finger flexor digitorum superficialis (FDS) tendons were outlined. Coordinate data were recorded and median nerve cross-sectional area, perimeter, aspect ratio of the minimal-enclosing rectangle, and circularity in extension and flexion positions were calculated. During index finger flexion, the tendon moves volarly while the nerve moves radially. With thumb flexion, the tendon moves volarly, but the median nerve moves toward the ulnar side. In both motions, the area and perimeter of the median nerve in flexion were smaller than in extension. Thus, during index finger or thumb flexion, the median nerve in a healthy human subject shifts away from the index finger FDS and FPL tendons while being compressed between the tendons and the flexor retinaculum in the carpal tunnel. We are planning to compare these data with measurements in patients with carpal tunnel syndrome (CTS) and believe that these parameters may be useful tools for the assessment of CTS and carpal tunnel mechanics with ultrasound in the future. PMID:20225286

  5. Ephaptic transmission between single nerve fibres in the spinal nerve roots of dystrophic mice.

    PubMed

    Rasminsky, M

    1980-08-01

    1. Ephaptic transmission was observed between spontaneously active single nerve fibres in the spinal nerve roots of dystrophic mice. 2. In the five ephaptically interacting pairs of fibres studied in detail, the conduction velocities in the exciting fibres were < 1 m/sec and the conduction velocities in the excited fibres were 2-10 m/sec in the immediate vicinity of the ephapses at 26-28 degrees C. 3. Membrane current analysis suggested that conduction was continuous in the exciting fibres. In some cases conduction away from the ephapse in the excited fibre was saltatory in at least one and possibly in both directions of transmission. 4. It is concluded that in at least some cases the direction of ephaptic transmission is from bare axon to myelinated axon. 5. Transmission time across the ephapses, measured as the interval between peaks of inward membrane current in exciting and excited fibres, was less than or equal to microseconds-240 microseconds. 6. Ephaptic transmission is not necessarily contingent upon the direction of propagation of the impulse in the exciting fibre. 7. Ephaptic transmission between two fibres can remain stable at frequencies of at least 70 Hz. 8. There may be multiple sites of spontaneous ectopic excitation in single dystrophic mouse spinal root axons. An impulse traversing a site of ectopic excitation may incite a subsequent burst of impulses to arise from that site following a delay of more than 100 msec. PMID:6255143

  6. Pediatric primitive intraneural synovial sarcoma of L-5 nerve root.

    PubMed

    Peia, Francesco; Gessi, Marco; Collini, Paola; Ferrari, Andrea; Erbetta, Alessandra; Valentini, Laura G

    2013-04-01

    Primitive intraneural synovial sarcomas are rare in children. The authors report the case of a 7-year-old girl affected by intraneural synovial sarcoma of a lumbar nerve root, the first such lesion in this location described in a child. The lesion mimicked a schwannoma clinically and radiologically. There was long-lasting leg pain in a radicular distribution, and a well-demarcated intraneural tumor was seen on MRI. On this basis, the first resection was conservative. However, histological examination documented a classic biphasic synovial sarcoma, which was confirmed by immunohistochemistry. After radical resection and adjuvant treatment, complete disease control was achieved and verified at 5-year follow-up. This case strongly suggests that early diagnosis and a multidisciplinary approach to this unusual spinal lesion are essential to achieving a better prognosis. PMID:23414131

  7. Ultrasonographic reference sizes of the median and ulnar nerves and the cervical nerve roots in healthy Japanese adults.

    PubMed

    Sugimoto, Takamichi; Ochi, Kazuhide; Hosomi, Naohisa; Mukai, Tomoya; Ueno, Hiroki; Takahashi, Tetsuya; Ohtsuki, Toshiho; Kohriyama, Tatsuo; Matsumoto, Masayasu

    2013-09-01

    The objective of this study was to identify, for practical use, ultrasonographic reference values for nerve sizes at multiple sites, including entrapment and non-entrapment sites along the median and ulnar nerves and among the cervical nerve roots. We verified reliable sites and site-based differences between the reference values. In addition, we found associations between the reference nerve sizes and several physical characteristics (gender, dominant hand, age, height, weight, body mass index [BMI] and wrist circumference). Nerves were measured bilaterally at 26 sites or levels in 60 healthy Japanese adults (29 males; age, 35.4 ± 9.7 y; BMI, 22.3 ± 3.6 kg/m(2); wrist circumference, 16.0 ± 1.3 cm on the right side and 15.9 ± 1.2 cm on the left side). The mean reference nerve sizes were 5.6-9.1 mm(2) along the median nerve, 4.1-6.7 mm(2) along the ulnar nerve and 2.14-3.39 mm among the cervical nerve roots. Multifactorial regression analyses revealed that the physical characteristics most strongly associated with nerve size were age, BMI and wrist circumference at the entrapment sites (F = 7.6, p < 0.01, at the pisiform bone level of the carpal tunnel; F = 15.1, p < 0.001, at the level of Guyon's canal), as well as wrist circumference and gender at the non-entrapment sites (F = 70.6, p < 0.001, along the median nerve; F = 24.7, p < 0.001, along the ulnar nerve). Our results suggest that the factors with the greatest influence on nerve size differed between entrapment and non-entrapment sites. Site-based differences in nerve size were determined using one-way analyses of variance (p < 0.001). Intra- and inter-observer reliability was highest for the median nerve, at both the distal wrist crease and mid-humerus; at the arterial split along the ulnar nerve; and at the fifth cervical nerve root level. No systematic error was indicated by Bland-Altman analysis; the coefficients of variation were 5.5%-9.2% for intra-observer reliability and 7.1%-8.7% for inter

  8. Brachial Plexopathy/Nerve Root Avulsion in a Football Player: The Role of Electrodiagnostics

    PubMed Central

    Radecki, Jeffrey; Wolfe, Scott W.; Strauss, Helene L.; Mintz, Douglas N.

    2008-01-01

    Electromyography (EMG) studies are a useful tool in anatomical localization of peripheral nerve and brachial plexus injuries. They are especially helpful in distinguishing between brachial plexopathy and nerve root injuries where surgical intervention may be indicated. EMG can also assist in providing prognostic information after nerve injury as well as after nerve repair. In this case report, a football player presented with weakness in his right upper limb after a traction/traumatic injury to the right brachial plexus. EMG studies revealed evidence of both pre- and postganglionic injury to multiple cervical roots. The injury was substantial enough to cause nerve root avulsions involving the C6 and C7 levels. Surgical referral led to nerve grafts targeted at regaining function in shoulder abduction and elbow flexion. After surgery, the patient’s progress was monitored utilizing EMG to assist in identifying true axonal regeneration. PMID:18751870

  9. Prolonged electrical stimulation causes no damage to sacral nerve roots in rabbits

    PubMed Central

    Yan, Peng; Yang, Xiaohong; Yang, Xiaoyu; Zheng, Weidong; Tan, Yunbing

    2014-01-01

    Previous studies have shown that, anode block electrical stimulation of the sacral nerve root can produce physiological urination and reconstruct urinary bladder function in rabbits. However, whether long-term anode block electrical stimulation causes damage to the sacral nerve root remains unclear, and needs further investigation. In this study, a complete spinal cord injury model was established in New Zealand white rabbits through T9–10 segment transection. Rabbits were given continuous electrical stimulation for a short period and then chronic stimulation for a longer period. Results showed that compared with normal rabbits, the structure of nerve cells in the anterior sacral nerve roots was unchanged in spinal cord injury rabbits after electrical stimulation. There was no significant difference in the expression of apoptosis-related proteins such as Bax, Caspase-3, and Bcl-2. Experimental findings indicate that neurons in the rabbit sacral nerve roots tolerate electrical stimulation, even after long-term anode block electrical stimulation. PMID:25206785

  10. The effect of the rotational angle on MR diffusion indices in nerves: Is the rms displacement of the slow-diffusing component a good measure of fiber orientation?

    NASA Astrophysics Data System (ADS)

    Bar-Shir, Amnon; Cohen, Yoram

    2008-01-01

    In recent years, much effort has been made to increase our ability to infer nerve fiber direction through the use of diffusion MR. The present study examines the effect of the rotational angle ( α), i.e. the angle between the diffusion sensitizing gradients and the main axis of the fibers in the nerves, on different NMR indices. The indices examined were the apparent diffusion coefficient (ADC), extracted from low b-values ( bmax ≈ 1200 s/mm 2), and the root mean square (rms) displacement of the fast and the slow-diffusing components extracted from high b-value q-space diffusion MR data. In addition, the effect of both the diffusion time and myelination was evaluated. We found that the most sensitive index to the rotational angle is the rms displacement of the slow-diffusing component extracted from the high b-value q-space diffusion MR experiment. For this component the rms displacement was nearly constant for α values ranging from -10° to +80° (where α = 0° is the z direction), but it changed dramatically when diffusion was measured nearly perpendicular to the nerve fiber direction, i.e., for α = 90 ± 10°. The ADC and the rms displacement of the fast-diffusing component exhibited only gradual changes, with a maximal change at α = 45 ± 15°. The sensitivity of the rms displacement of the slow-diffusing component to the rotational angle was found to be higher at longer diffusion times and in mature fully myelinated nerves. The relevance of these observations for determining the fiber direction is briefly discussed.

  11. Spinal nerve root haemangioblastoma associated with reactive polycythemia.

    PubMed

    Law, Eric K C; Lee, Ryan K L; Griffith, James F; Siu, Deyond Y W; Ng, Ho Keung

    2014-01-01

    Haemangioblastomas are uncommon tumours that usually occur in the cerebellum and, less commonly, in the intramedullary spinal cord. The extramedullary spinal canal is an uncommon location for these tumours. Also haemangioblastoma at this site is not known to be associated with polycythemia. We present the clinical, imaging, and histological findings of an adult patient with extramedullary spinal haemangioblastoma and reactive polycythemia. Radiography and computed tomography (CT) revealed a medium-sized tumour that most likely arose from an extramedullary spinal nerve root. This tumour appeared to be slow growing as evidenced by the accompanying well-defined bony resorption with a sclerotic rim and mild neural foraminal widening. Magnetic resonance imaging revealed prominent flow voids consistent with tumoural hypervascularity. CT-guided biopsy was performed. Although preoperative angiographic embolisation was technically successful, excessive intraoperative tumour bleeding necessitated tumour debulking rather than complete tumour resection. Histology of the resected specimen revealed haemangioblastoma. Seven months postoperatively, the patients back pain and polycythemia have resolved. PMID:25431722

  12. A widely displaced Galeazzi-equivalent lesion with median nerve compromise

    PubMed Central

    Galanopoulos, Ilias; Fogg, Quentin; Ashwood, Neil; Fu, Katherine

    2012-01-01

    We present the case of a 14-year-old boy with a right distal radial fracture accompanied by a severely displaced complete distal ulnar physeal separation and associated median nerve compromise. This injury is known as Galeazzi-equivalent lesion in children and is an extremely rare injury associated with growth arrest. Recognition of the lesion can be difficult but wide displacement may be associated with other significant injuries such as neurovascular compromise. Prompt intervention reversed the neurological symptoms. At 10-month postoperation there was neither growth arrest nor loss of motion. Complete separation of the ulna physis remains often because of soft tissue interposition or capsule problems and prompt reduction is recommended in the literature as a priority. PMID:22907852

  13. Thoracic Nerve Root Schwannoma Filling the Spinal Canal Almost Entirely Without any Neurological Deficits

    PubMed Central

    Godlewski, Bartosz; Klauz, Grzegorz; Czepko, Ryszard

    2016-01-01

    Introduction Spinal tumours may be classified in three groups: 1) extradural, 2) intradural extramedullary and 3) intramedullary spinal cord tumours. Intradural extramedullary tumours arise from the leptomeninges or nerve roots and include schwannomas. A schwannoma is usually a firm grey-whitish tumour growing near a nerve trunk or ramus. It can be separated from the nerve without damaging neural tissue. Schwannomas are usually solitary tumours. Case Presentation We present the case of a 37-year-old male who underwent surgery for a tumour in the upper thoracic segment of the spinal canal. Although the tumour filled the spinal canal almost entirely, the patient did not manifest any neurological deficits. During the surgery, the tumour was removed completely. A histological examination confirmed a benign schwannoma lesion (WHO G1). Conclusions The question whether doctors are keen to order more diagnostic investigations (including both laboratory and imaging studies) than are necessary is often asked in clinical practice. The cost factor is also important. Not every patient with back pain is referred for an MRI study in the absence of characteristic neurological signs. The case of our patient, however, speaks in favour of early referral for such diagnostic modalities. Appropriate imaging studies, even in patients presenting with no neurological deficits, may help detect pathologies than can lead to severe disability. A spinal canal tumour filling the spinal canal almost entirely and displacing the spinal cord could cause spinal cord damage at any time with all the dire consequences such as paraplegia and loss of the ability to walk. PMID:27110539

  14. [Clinical study of the relationship between the lateral recesses and the nerve roots].

    PubMed

    Lian, P; Sun, R; Jia, L

    1997-04-01

    To explicate the relationship and the clinical signification between the normal or narrow lateral recesses and the nerve roots, we measured the diameter of the entrans zone of the lateral recess, the interval between the upper articular processes and the interval between the nerve root and ab line on 50 normal cases, 43 narrow cases and 32 stenosis cases with VIDS image analysis system. The results showed that the nerve root was in the center side of the ab line in the normal station, with the degrees of the degeneration and cohesion ncreasing, the nerve root was in the lateral recess side of the ab line, and was compressed by the lateral recess. The authors considered that the real clinical signification of the entrance zone of the lateral recess was danger to the nerve root, but the deciding factors were the degrees of the degeneration and cohesion of the upper articular processes. The pathological conditions that resulted in the stenosis of the lateral recess and dangered the nerve root such as disc, flavum ligament and posterior port of the fibra ring were discussed in the article. PMID:10374545

  15. The Relation Between Rotation Deformity and Nerve Root Stress in Lumbar Scoliosis

    NASA Astrophysics Data System (ADS)

    Kim, Ho-Joong; Lee, Hwan-Mo; Moon, Seong-Hwan; Chun, Heoung-Jae; Kang, Kyoung-Tak

    Even though several finite element models of lumbar spine were introduced, there has been no model including the neural structure. Therefore, the authors made the novel lumbar spine finite element model including neural structure. Using this model, we investigated the relation between the deformity pattern and nerve root stress. Two lumbar models with different types of curve pattern (lateral bending and lateral bending with rotation curve) were made. In the model of lateral bending curves without rotation, the principal compressive nerve root stress on the concave side was greater than the principal tensile stress on the convex side at the apex vertebra. Contrarily, in the lateral bending curve with rotational deformity, the nerve stress on the convex side was higher than that on the concave side. Therefore, this study elicit that deformity pattern could have significantly influence on the nerve root stress in the lumbar spine.

  16. Skin Sympathetic Nerve Activity is Modulated during Slow Sinusoidal Linear Displacements in Supine Humans

    PubMed Central

    Bolton, Philip S.; Hammam, Elie; Kwok, Kenny; Macefield, Vaughan G.

    2016-01-01

    Low-frequency sinusoidal linear acceleration (0.08 Hz, ±4 mG) modulates skin sympathetic nerve activity (SSNA) in seated subjects (head vertical), suggesting that activation of the utricle in the peripheral vestibular labyrinth modulates SSNA. The aim of the current study was to determine whether SSNA is also modulated by input from the saccule. Tungsten microelectrodes were inserted into the common peroneal nerve to record oligounitary SSNA in 8 subjects laying supine on a motorized platform with the head aligned with the longitudinal axis of the body. Slow sinusoidal (0.08 Hz, 100 cycles) linear acceleration-decelerations (peak ±4 mG) were applied rostrocaudally to predominately activate the saccules, or mediolaterally to predominately activate the utricles. Cross-correlation histograms were constructed between the negative-going sympathetic spikes and the positive peaks of the sinusoidal stimuli. Sinusoidal linear acceleration along the rostrocaudal axis or mediolateral axis both resulted in sinusoidal modulation of SSNA (Median, IQR 27.0, 22–33% and 24.8, 17–39%, respectively). This suggests that both otolith organs act on sympathetic outflow to skin and muscle in a similar manner during supine displacements. PMID:26909019

  17. Skin Sympathetic Nerve Activity is Modulated during Slow Sinusoidal Linear Displacements in Supine Humans.

    PubMed

    Bolton, Philip S; Hammam, Elie; Kwok, Kenny; Macefield, Vaughan G

    2016-01-01

    Low-frequency sinusoidal linear acceleration (0.08 Hz, ±4 mG) modulates skin sympathetic nerve activity (SSNA) in seated subjects (head vertical), suggesting that activation of the utricle in the peripheral vestibular labyrinth modulates SSNA. The aim of the current study was to determine whether SSNA is also modulated by input from the saccule. Tungsten microelectrodes were inserted into the common peroneal nerve to record oligounitary SSNA in 8 subjects laying supine on a motorized platform with the head aligned with the longitudinal axis of the body. Slow sinusoidal (0.08 Hz, 100 cycles) linear acceleration-decelerations (peak ±4 mG) were applied rostrocaudally to predominately activate the saccules, or mediolaterally to predominately activate the utricles. Cross-correlation histograms were constructed between the negative-going sympathetic spikes and the positive peaks of the sinusoidal stimuli. Sinusoidal linear acceleration along the rostrocaudal axis or mediolateral axis both resulted in sinusoidal modulation of SSNA (Median, IQR 27.0, 22-33% and 24.8, 17-39%, respectively). This suggests that both otolith organs act on sympathetic outflow to skin and muscle in a similar manner during supine displacements. PMID:26909019

  18. More nerve root injuries occur with minimally invasive lumbar surgery: Let's tell someone

    PubMed Central

    Epstein, Nancy E.

    2016-01-01

    Background: In a recent study entitled: “More nerve root injuries occur with minimally invasive lumbar surgery, especially extreme lateral interbody fusion (XLIF): A review”, Epstein documented that more nerve root injuries occurred utilizing minimally invasive surgery (MIS) versus open lumbar surgery for diskectomy, decompression of stenosis (laminectomy), and/or fusion for instability. Methods: In large multicenter Spine Patient Outcomes Research Trial reviews performed by Desai et al., nerve root injury with open diskectomy occurred in 0.13–0.25% of cases, occurred in 0% of laminectomy/stenosis with/without fusion cases, and just 2% for open laminectomy/stenosis/degenerative spondylolisthesis with/without fusion. Results: In another MIS series performed largely for disc disease (often contained nonsurgical disc herniations, therefore unnecessary procedures) or spondylolisthesis, the risk of root injury was 2% for transforaminal lumbar interbody fusion (TLIF) versus 7.8% for posterior lumbar interbody fusion (PLIF). Furthermore, the high frequencies of radiculitis/nerve root/plexus injuries incurring during anterior lumbar interbody fusions (ALIF: 15.8%) versus extreme lumbar interbody fusions (XLIF: 23.8%), addressing disc disease, failed back surgery, and spondylolisthesis, were far from acceptable. Conclusions: The incidence of nerve root injuries following any of the multiple MIS lumbar surgical techniques (TLIF/PLIF/ALIF/XLIF) resulted in more nerve root injuries when compared with open conventional lumbar surgical techniques. Considering the majority of these procedures are unnecessarily being performed for degenerative disc disease alone, spine surgeons should be increasingly asked why they are offering these operations to their patients? PMID:26904373

  19. New Treatments for Spinal Nerve Root Avulsion Injury

    PubMed Central

    Carlstedt, Thomas

    2016-01-01

    Further progress in the treatment of the longitudinal spinal cord injury has been made. In an inverted translational study, it has been demonstrated that return of sensory function can be achieved by bypassing the avulsed dorsal root ganglion neurons. Dendritic growth from spinal cord sensory neurons could replace dorsal root ganglion axons and re-establish a reflex arch. Another research avenue has led to the development of adjuvant therapy for regeneration following dorsal root to spinal cord implantation in root avulsion injury. A small, lipophilic molecule that can be given orally acts on the retinoic acid receptor system as an agonist. Upregulation of dorsal root ganglion regenerative ability and organization of glia reaction to injury were demonstrated in treated animals. The dual effect of this substance may open new avenues for the treatment of root avulsion and spinal cord injuries. PMID:27602018

  20. New Treatments for Spinal Nerve Root Avulsion Injury.

    PubMed

    Carlstedt, Thomas

    2016-01-01

    Further progress in the treatment of the longitudinal spinal cord injury has been made. In an inverted translational study, it has been demonstrated that return of sensory function can be achieved by bypassing the avulsed dorsal root ganglion neurons. Dendritic growth from spinal cord sensory neurons could replace dorsal root ganglion axons and re-establish a reflex arch. Another research avenue has led to the development of adjuvant therapy for regeneration following dorsal root to spinal cord implantation in root avulsion injury. A small, lipophilic molecule that can be given orally acts on the retinoic acid receptor system as an agonist. Upregulation of dorsal root ganglion regenerative ability and organization of glia reaction to injury were demonstrated in treated animals. The dual effect of this substance may open new avenues for the treatment of root avulsion and spinal cord injuries. PMID:27602018

  1. A Case of Delusional Parasitosis Associated with Multiple Lesions at the Root of Trigeminal Nerve

    PubMed Central

    Azad, Alvi; Scholma, Randal S.; Joshi, Kaustubh G.

    2010-01-01

    The authors present a patient with multiple pontine lesions who exhibited symptoms consistent with delusional parasitosis. The trigeminal nerve nuclei are located throughout the brainstem. Pathology in either the nuclei or the branches of the fifth cranial nerve has been associated with both sensory and motor disturbances. Delusional parasitosis is a condition in which the patient has the firm belief that small, living organisms have infested his or her skin or other organs. To our knowledge, this is the first case report of delusional parasitosis associated with lesions at the root of the trigeminal nerve. PMID:20877531

  2. [Physiological approach to peripheral neuropathy. Conventional nerve conduction studies and magnetic motor root stimulation].

    PubMed

    Ugawa, Yoshikazu

    2004-11-01

    In this communication, I first show some points we should mind in the conventional peripheral nerve conduction studies and later present clinical usefulness of motor root stimulation for peripheral neuropathy. CONVENTIONAL NERVE CONDUCTION STUDIES (NCS): The most important point revealed by the conventional NCSs is whether neuropathy is due to axonal degeneration or demyelinating process. Precise clinical examination with this neurophysiological information leads us to a diagnosis and treatment. Poor clinical examination makes these findings useless. Long standing axonal degeneration sometimes induces secondary demyelination at the most distal part of involved nerves. On the other hand, severe segmental demyelination often provokes secondary axonal degeneration at distal parts to the site of demyelination. These secondary changes show the same abnormal neurophysiological findings as those of the primary involvement. We should be careful of this possibility when interpreting the results of NCS. NCS of sensory nerves is not good at revealing demyelinating process. Mild temporal dispersion of potentials often reduces an amplitude of SNAP or loss of responses, which usually suggests axonal degeneration, because of short duration of sensory nerve potentials. MOTOR ROOT STIMULATION IN PERIPHERAL NEUROPATHY: Magnetic stimulation with a coil placed over the spine activates motor roots and evokes EMG responses from upper and lower limb muscles. The site of activation with this method was determined to be where the motor roots exit from the spinal canal (intervertebral foramina) (J Neurol Neurosurg Psychiatry 52 (9): 1025-1032, 1989) because induced currents are very dense at such a foramen made by electric resistant bones. In several kinds of peripheral neuropathy, this method has been used to detect a lesion at a proximal part of the peripheral nerves which can not be detected by the conventional NCSs. I present a few cases in whom motor root stimulation had a clinical

  3. Lumbar nerve root avulsions with secondary ipsilateral hip dysplasia in a child.

    PubMed

    Polyzoidis, Konstandinos; Petropoulou, Calliope; Argyropoulou, Paraskevi I; Vranos, Georgios; Sarmas, Ioannis; Argyropoulou, Maria I

    2002-09-01

    We report on an 8-year-old child with avulsions of the left L3, L4 and L5 nerve roots and traumatic meningoceles that were not associated with lumbar spine or pelvic girdle fractures. The patient had a history of a road traffic accident. Plain radiographs of the pelvis revealed left hip dysplasia. The magnetic resonance imaging findings of the lumbar spine are illustrated. The pathogenesis of lumbar nerve root avulsions and their association with ipsilateral hip dysplasia are discussed. PMID:12221453

  4. A conduction block in sciatic nerves can be detected by magnetic motor root stimulation.

    PubMed

    Matsumoto, Hideyuki; Konoma, Yuko; Fujii, Kengo; Hanajima, Ritsuko; Terao, Yasuo; Ugawa, Yoshikazu

    2013-08-15

    Useful diagnostic techniques for the acute phase of sciatic nerve palsy, an entrapment neuropathy, are not well established. The aim of this paper is to demonstrate the diagnostic utility of magnetic sacral motor root stimulation for sciatic nerve palsy. We analyzed the peripheral nerves innervating the abductor hallucis muscle using both electrical stimulations at the ankle and knee and magnetic stimulations at the neuro-foramina and conus medullaris levels in a patient with sciatic nerve palsy at the level of the piriformis muscle due to gluteal compression related to alcohol consumption. On the fourth day after onset, magnetic sacral motor root stimulation using a MATS coil (the MATS coil stimulation method) clearly revealed a conduction block between the knee and the sacral neuro-foramina. Two weeks after onset, needle electromyography supported the existence of the focal lesion. The MATS coil stimulation method clearly revealed a conduction block in the sciatic nerve and is therefore a useful diagnostic tool for the abnormal neurophysiological findings associated with sciatic nerve palsy even at the acute phase. PMID:23809191

  5. Dorsal root ganglion transcriptome analysis following peripheral nerve injury in mice

    PubMed Central

    Wu, Shaogen; Marie Lutz, Brianna; Miao, Xuerong; Liang, Lingli; Mo, Kai; Chang, Yun-Juan; Du, Peicheng; Soteropoulos, Patricia; Tian, Bin; Kaufman, Andrew G.; Bekker, Alex; Hu, Yali

    2016-01-01

    Background Peripheral nerve injury leads to changes in gene expression in primary sensory neurons of the injured dorsal root ganglia. These changes are believed to be involved in neuropathic pain genesis. Previously, these changes have been identified using gene microarrays or next generation RNA sequencing with poly-A tail selection, but these approaches cannot provide a more thorough analysis of gene expression alterations after nerve injury. Methods The present study chose to eliminate mRNA poly-A tail selection and perform strand-specific next generation RNA sequencing to analyze whole transcriptomes in the injured dorsal root ganglia following spinal nerve ligation. Quantitative real-time reverse transcriptase polymerase chain reaction assay was carried out to verify the changes of some differentially expressed RNAs in the injured dorsal root ganglia after spinal nerve ligation. Results Our results showed that more than 50 million (M) paired mapped sequences with strand information were yielded in each group (51.87 M–56.12 M in sham vs. 51.08 M–57.99 M in spinal nerve ligation). Six days after spinal nerve ligation, expression levels of 11,163 out of a total of 27,463 identified genes in the injured dorsal root ganglia significantly changed, of which 52.14% were upregulated and 47.86% downregulated. The largest transcriptional changes were observed in protein-coding genes (91.5%) followed by noncoding RNAs. Within 944 differentially expressed noncoding RNAs, the most significant changes were seen in long interspersed noncoding RNAs followed by antisense RNAs, processed transcripts, and pseudogenes. We observed a notable proportion of reads aligning to intronic regions in both groups (44.0% in sham vs. 49.6% in spinal nerve ligation). Using quantitative real-time polymerase chain reaction, we confirmed consistent differential expression of selected genes including Kcna2, Oprm1 as well as lncRNAs Gm21781 and 4732491K20Rik following spinal nerve

  6. Mechanical properties of nerve roots and rami radiculares isolated from fresh pig spinal cords

    PubMed Central

    Nishida, Norihiro; Kanchiku, Tsukasa; Ohgi, Junji; Ichihara, Kazuhiko; Chen, Xian; Taguchi, Toshihiko

    2015-01-01

    No reports have described experiments designed to determine the strength characteristics of spinal nerve roots and rami radiculares for the purpose of explaining the complexity of symptoms of medullary cone lesions and cauda equina syndrome. In this study, to explain the pathogenesis of cauda equina syndrome, monoaxial tensile tests were performed to determine the strength characteristics of spinal nerve roots and rami radiculares, and analysis was conducted to evaluate the stress-strain relationship and strength characteristics. Using the same tensile test device, the nerve root and ramus radiculares isolated from the spinal cords of pigs were subjected to the tensile test and stress relaxation test at load strain rates of 0.1, 1, 10, and 100 s-1 under identical settings. The tensile strength of the nerve root was not rate dependent, while the ramus radiculares tensile strength tended to decrease as the strain rate increased. These findings provide important insights into cauda equina symptoms, radiculopathy, and clinical symptoms of the medullary cone. PMID:26807127

  7. The Role of Selective Nerve Root Block in the Treatment of Lumbar Radicular Leg Pain.

    PubMed

    Jonayed, S A; Kamruzzaman, M; Saha, M K; Alam, S; Akter, S

    2016-01-01

    The objective of this retrospective study was to investigate the clinical effectiveness of nerve root blocks (i.e., periradicular injection of Lidocaine and triamcinolone) for lumbar monoradiculopathy in patients with a mild neurological deficit in National Institute of Traumatology & Orthopaedic Rehabilitation (NITOR), Dhaka, Bangladesh from March 2014 to December 2014. We Included 24 patients (32-74 years) with a minor sensory/motor deficit and an unequivocal MRI finding (18 disc herniations, 6 foraminal stenosis) treated with a selective nerve root block. Based on the clinical and imaging findings, surgery (decompression of the nerve root) was justifiable in all cases. Seventeen patients (87%) had rapid (1-4 days) and substantial regression of pain, four required a repeat injection. Sixty percent (60%) of the patients with disc herniation or foraminal stenosis had permanent resolution of pain, so that an operation was avoided over an average of 6 months (2-9 months) follow-up. Nerve root blocks are very effective in the non-operative treatment of minor monoradiculopathy and should be recommended as the initial treatment of choice for this condition. PMID:26931264

  8. Intraoral management of iatrogenically displaced lower third molar roots in the sublingual space: a report of 2 cases

    PubMed Central

    Zhao, Sufeng; Huang, Zheng; Geng, Tengyu; Huang, Lanzhu

    2015-01-01

    Surgical removal of the mandibular third molars is one of the most common procedures performed by dentists, as well as by oral and maxillofacial surgeons. Accidental displacement of teeth or roots into the fascial spaces, during surgical removal of the mandibular third molars, is a rare, but serious complication. Herein, we present 2 cases of iatrogenically displaced mandibular third molar roots into the sublingual space, which were successfully removed under local anesthesia intraorally. In addition to methods to minimize the risk of accidental tooth or root displacement, the importance of recognizing this complication and the methods of retrieval are also discussed. PMID:26770616

  9. Migratory Reed Warblers Need Intact Trigeminal Nerves to Correct for a 1,000 km Eastward Displacement.

    PubMed

    Kishkinev, Dmitry; Chernetsov, Nikita; Heyers, Dominik; Mouritsen, Henrik

    2013-01-01

    Several studies have shown that experienced night-migratory songbirds can determine their position, but it has remained a mystery which cues and sensory mechanisms they use, in particular, those used to determine longitude (east-west position). One potential solution would be to use a magnetic map or signpost mechanism like the one documented in sea turtles. Night-migratory songbirds have a magnetic compass in their eyes and a second magnetic sense with unknown biological function involving the ophthalmic branch of the trigeminal nerve (V1). Could V1 be involved in determining east-west position? We displaced 57 Eurasian reed warblers (Acrocephalus scirpaceus) with or without sectioned V1. Sham operated birds corrected their orientation towards the breeding area after displacement like the untreated controls did. In contrast, V1-sectioned birds did not correct for the displacement. They oriented in the same direction after the displacement as they had done at the capture site. Thus, an intact ophthalmic branch of the trigeminal nerve is necessary for detecting the 1,000 km eastward displacement in this night-migratory songbird. Our results suggest that V1 carries map-related information used in a large-scale map or signpost sense that the reed warblers needed to determine their approximate geographical position and/or an east-west coordinate. PMID:23840374

  10. The Incidence of Lumbar Discectomy after Epidural Steroid Injections or Selective Nerve Root Blocks

    PubMed Central

    Mroz, Thomas; Lieberman, Isador

    2015-01-01

    Background The purpose of this study was to determine the use of Central Epidural Steroid Injections (ESI) and Selective Nerve Root Blocks (SNRB) along with the crossover rate to lumbar discectomy in patients with a lumbar disc herniation using retrospective records database search. Butterman et al found a crossover rate for patients with symptomatic disc herniations treated with ESI of 54% (27/50), while Riew similarly found a 53% (29/55) crossover patients receiving SNRB. Methods The database was searched in a sequential Boolean style for patients with the diagnosis of a lumbar disc herniation (Displaced Lumbar Disc - 722.1) and a SNRB (64483) or ESI (62311) who subsequently underwent a Lumbar Discectomy (63030) over a three year time period from January 2004 through December 2006. Statistical analysis was preformed examining the impact of injection type, age, location, gender, and year. Results Of 482,893 patients with the diagnosis of a disc herniation, 27,799(5.76%) underwent a lumbar discectomy. The 29,941 patients who received at least one SNRB for a disc herniation, 10.80% later underwent a lumbar discectomy. The 41,420 patients who received at least one ESI for a disc herniation 9.34% later underwent a lumbar discectomy. There was a noted increase in injection procedures, particularly SNRB during the study with a greater than 50% increase. Conclusions Our examination found a much smaller, but similar crossover rate to surgery between both injection methods, which argues against one method being more effective than another in avoiding surgery. It is likely that patients are receiving these procedures more frequently during the course of conservative treatment for a disc herniation. Level of Evidence This was a Level III study. PMID:26056627

  11. Global analysis of transcriptome in dorsal root ganglia following peripheral nerve injury in rats.

    PubMed

    Gong, Leilei; Wu, Jiancheng; Zhou, Songlin; Wang, Yaxian; Qin, Jing; Yu, Bin; Gu, Xiaosong; Yao, Chun

    2016-09-01

    Peripheral nervous system has intrinsic regeneration ability after injury, accompanied with the coordination of numerous cells, molecules and signaling pathways. These post-injury biological changes are complex with insufficient understanding. Thus, to obtain a global perspective of changes following nerve injury and to elucidate the mechanisms underlying nerve regeneration are of great importance. By RNA sequencing, we detected transcriptional changes in dorsal root ganglia (DRG) neurons at 0 h, 3 h, 9 h, 1 d, 4 d and 7 d following sciatic nerve crush injury in rats. Differentially expressed genes were then selected and classified into major clusters according to their expression patterns. Cluster 2 (with genes high expressed before 9 h and then down expressed) and cluster 6 (combination of cluster 4 and 5 with genes low expressed before 1 d and then up expressed) were underwent GO annotation and KEGG pathway analysis. Gene act networks were then constructed for these two clusters and the expression of pivotal genes was validated by quantitative real-time PCR. This study provided valuable information regarding the transcriptome changes in DRG neurons following nerve injury, identified potential genes that could be used for improving axon regeneration after nerve injury, and facilitated to elucidate the biological process and molecular mechanisms underlying peripheral nerve injury. PMID:27450809

  12. Synovial cyst--an unusual cause of nerve root compression. A case report.

    PubMed

    Hammer, A J

    1988-01-01

    An elderly woman presented with a tense, synovia-lined ganglion, associated with the left L3/L4 apophyseal joint, which protruded posteriorly and caudally through the joint capsule and extended anteriorly and cephally into the neural canal. The intraspinal extension produced a compression radiculopathy of the L3 nerve root. Removal of the cyst produced acute and dramatic alleviation of the symptoms. PMID:3340901

  13. Spinal Cord and Spinal Nerve Root Involvement (Myeloradiculopathy) in Tuberculous Meningitis

    PubMed Central

    Gupta, Rahul; Garg, Ravindra Kumar; Jain, Amita; Malhotra, Hardeep Singh; Verma, Rajesh; Sharma, Praveen Kumar

    2015-01-01

    Abstract Most of the information about spinal cord and nerve root involvement in tuberculous meningitis is available in the form of isolated case reports or case series. In this article, we evaluated the incidence, predictors, and prognostic impact of spinal cord and spinal nerve root involvement in tuberculous meningitis. In this prospective study, 71 consecutive patients of newly diagnosed tuberculous meningitis were enrolled. In addition to clinical evaluation, patients were subjected to magnetic resonance imaging (MRI) of brain and spine. Patients were followed up for at least 6 months. Out of 71 patients, 33 (46.4%) had symptoms/signs of spinal cord and spinal nerve root involvement, 22 (30.9%) of whom had symptoms/signs at enrolment. Eleven (15.4%) patients had paradoxical involvement. Paraparesis was present in 22 (31%) patients, which was of upper motor neuron type in 6 (8.4%) patients, lower motor neuron type in 10 (14%) patients, and mixed type in 6 (8.4%) patients. Quadriparesis was present in 3 (4.2%) patients. The most common finding on spinal MRI was meningeal enhancement, seen in 40 (56.3%) patients; in 22 (30.9%), enhancement was present in the lumbosacral region. Other MRI abnormalities included myelitis in 16 (22.5%), tuberculoma in 4 (5.6%), cerebrospinal fluid (CSF) loculations in 4 (5.6%), cord atrophy in 3 (4.2%), and syrinx in 2 (2.8%) patients. The significant predictor associated with myeloradiculopathy was raised CSF protein (>250 mg/dL). Myeloradiculopathy was significantly associated with poor outcome. In conclusion, spinal cord and spinal nerve root involvement in tuberculous meningitis is common. Markedly raised CSF protein is an important predictor. Patients with myeloradiculopathy have poor outcome. PMID:25621686

  14. Extramedullary Conus Ependymoma Involving a Lumbar Nerve Root with Filum Terminale Attachment

    PubMed Central

    Moriwaki, Takashi; Iwatsuki, Koichi; Ohnishi, Yu-ichiro; Ninomiya, Koshi; Yoshimine, Toshiki

    2015-01-01

    PURPOSE In the current report, we describe a case of an extramedullary ependymoma involving a lumbar nerve root near conus medullaris. Spinal ependymomas commonly present as intramedullary tumors in the cervical or thoracic cord or as tumors arising from the conus medullaris or the filum terminale. In this case, we showed an extramedullary conus ependymoma involving a lumbar nerve root with filum terminale attachment. CASE PRESENTATION A 69-year-old woman presented with lower back pain, but without sensory disturbance or motor weakness in her lower extremities. CLINICAL ASSESSMENT Magnetic resonance imaging revealed an intradural mass at T12–L1 at the conus medullaris, which was totally resected. Histopathology revealed a non-myxopapillary ependymoma (WHO grade 2). Postoperatively, the patient did well and displayed no neurological deficits. Moreover, no radiotherapy was required. CONCLUSIONS This report documented a rare case of intradural extramedullary ependymoma located at the conus medullaris, involving the lumbar nerve root, and attached to the filum terminale. Although extramedullary ependymomas at this region are more frequently classified as myxopapillary, histopathological examination revealed this tumor as a non-myxopapillary ependymoma. PMID:26648765

  15. Potential risk of thermal damage to cervical nerve roots by a high-speed drill.

    PubMed

    Hosono, N; Miwa, T; Mukai, Y; Takenaka, S; Makino, T; Fuji, T

    2009-11-01

    Using the transverse processes of fresh porcine lumbar spines as an experimental model we evaluated the heat generated by a rotating burr of a high-speed drill in cutting the bone. The temperature at the drilled site reached 174 degrees C with a diamond burr and 77 degrees C with a steel burr. With water irrigation at a flow rate of 540 ml/hr an effective reduction in the temperature was achieved whereas irrigation with water at 180 ml/hr was much less effective. There was a significant negative correlation between the thickness of the residual bone and the temperature measured at its undersurface adjacent to the drilling site (p < 0.001). Our data suggest that tissues neighbouring the drilled bone, especially nerve roots, can be damaged by the heat generated from the tip of a high-speed drill. Nerve-root palsy, one of the most common complications of cervical spinal surgery, may be caused by thermal damage to nerve roots arising in this manner. PMID:19880905

  16. Robot-assisted C7 nerve root transfer from the contralateral healthy side: A preliminary cadaver study.

    PubMed

    Jiang, Su; Ichihara, Satoshi; Prunières, Guillaume; Peterson, Brett; Facca, Sybille; Xu, Wen-Dong; Liverneaux, Philippe

    2016-04-01

    Patients with cerebral palsy and spastic hemiplegia may have extremely poor upper extremity function. Unfortunately, many current therapies and treatments for patients with spastic hemiplegia offer very limited improvements. One innovative technique for treating these patients is the use a contralateral C7 nerve root transfer to neurotize the C7 nerve root in the affected limb. This may result not only in less spasticity in the affected limb, but also improved control and motor function vis-a-vis the new connection to the normal cerebral hemisphere. However, contralateral C7 transfers can require large incisions and long nerve grafts. The aim of this study was to test the feasibility of a contralateral C7 nerve root transfer procedure with the use of a prevertebral minimally invasive robot-assisted technique. In a cadaver, both sides of the C7 root were dissected. The right recipient C7 root was resected as proximally as possible, while the left donor C7 root was resected as distally as possible. With the use of the da Vinci (®) SI surgical robot (Intuitive Surgical ™, Sunnyvale, CA, USA), we were able to eliminate the large incision and use a much shorter nerve graft when performing contralateral C7 nerve transfer. PMID:27117122

  17. Intraoral management of displaced root into submandibular space under local anaesthesia –A case report and review of literature

    PubMed Central

    Jolly, Satnam Singh; Rattan, Vidya; Rai, Sachin Kumar

    2014-01-01

    Accidental displacement of an impacted third molar, either a root fragment, crown, or the entire tooth, is a rare complication that occurs during exodontia. The most common sites of dislodgment of an impacted mandibular third molar fragment are the sublingual, submandibular, and pterygomandibular spaces. Removal of a displaced root tip from these spaces may be complex due to poor visualization and limited access. A thorough evaluation of all significant risk factors must be performed in advance to prevent complications. This paper reports the case of a patient who presented with a mandibular third molar root that was displaced into submandibular space. The case was managed intraorally under local anaesthesia and review of the literature. PMID:25382952

  18. Pulsed electrical stimulation protects neurons in the dorsal root and anterior horn of the spinal cord after peripheral nerve injury.

    PubMed

    Pei, Bao-An; Zi, Jin-Hua; Wu, Li-Sheng; Zhang, Cun-Hua; Chen, Yun-Zhen

    2015-10-01

    Most studies on peripheral nerve injury have focused on repair at the site of injury, but very few have examined the effects of repair strategies on the more proximal neuronal cell bodies. In this study, an approximately 10-mm-long nerve segment from the ischial tuberosity in the rat was transected and its proximal and distal ends were inverted and sutured. The spinal cord was subjected to pulsed electrical stimulation at T10 and L3, at a current of 6.5 mA and a stimulation frequency of 15 Hz, 15 minutes per session, twice a day for 56 days. After pulsed electrical stimulation, the number of neurons in the dorsal root ganglion and anterior horn was increased in rats with sciatic nerve injury. The number of myelinated nerve fibers was increased in the sciatic nerve. The ultrastructure of neurons in the dorsal root ganglion and spinal cord was noticeably improved. Conduction velocity of the sciatic nerve was also increased. These results show that pulsed electrical stimulation protects sensory neurons in the dorsal root ganglia as well as motor neurons in the anterior horn of the spinal cord after peripheral nerve injury, and that it promotes the regeneration of peripheral nerve fibers. PMID:26692864

  19. Pulsed electrical stimulation protects neurons in the dorsal root and anterior horn of the spinal cord after peripheral nerve injury

    PubMed Central

    Pei, Bao-an; Zi, Jin-hua; Wu, Li-sheng; Zhang, Cun-hua; Chen, Yun-zhen

    2015-01-01

    Most studies on peripheral nerve injury have focused on repair at the site of injury, but very few have examined the effects of repair strategies on the more proximal neuronal cell bodies. In this study, an approximately 10-mm-long nerve segment from the ischial tuberosity in the rat was transected and its proximal and distal ends were inverted and sutured. The spinal cord was subjected to pulsed electrical stimulation at T10 and L3, at a current of 6.5 mA and a stimulation frequency of 15 Hz, 15 minutes per session, twice a day for 56 days. After pulsed electrical stimulation, the number of neurons in the dorsal root ganglion and anterior horn was increased in rats with sciatic nerve injury. The number of myelinated nerve fibers was increased in the sciatic nerve. The ultrastructure of neurons in the dorsal root ganglion and spinal cord was noticeably improved. Conduction velocity of the sciatic nerve was also increased. These results show that pulsed electrical stimulation protects sensory neurons in the dorsal root ganglia as well as motor neurons in the anterior horn of the spinal cord after peripheral nerve injury, and that it promotes the regeneration of peripheral nerve fibers. PMID:26692864

  20. Experimental studies on the effect of chymopapain on nerve root compression caused by intervertebral disk material.

    PubMed

    Krempen, J F; Minnig, D I; Smith, B S

    1975-01-01

    Chymopapain degrades the nucleus pulposus portion of the intervertebral disk of rabbits. The degradation is not grossly visible until 15 days post-injection. Depolymerization of the chondromucoprotein and decreases in the ability of a disk to imbibe fluid, is, in effect, a "chemical decompression" of the nucleur pulposus. The enzyme must come into direct contact with the chondromucoprotein complex of the disk material, and to a significant extent also must reach the area of disk material adjacent to the herniated annulus. Rapid depolymerization of the chondromucoprotein complex on a biomechanical level, and "decompression" of disk material on a biomechanical level can be correlated with relief of pain in all types of disk herniation in human beings. A primary biochemical change in the disk material would lead to a secondary decrease in inflammation if the change led to a "decompression" of the chondromucoprotein. Since the primary effect of chymopapain is on the chondromucoprotein of the disk, beneficial results would not be expected if nerve root compression is due to bony impingement or scar tissue following previous surgery. Chymopapain did not seem to possess any anti-inflammatory properties when bone was used as an irritant under a nerve root. However, this was technically difficult to evaluate and the possibility that chymopapain may also interfere with a chemical mediator of pain or interfere directly with an inflammatory reaction secondary to root compression can not be excluded. PMID:1126086

  1. Correlation of Foraminal Area and Response to Cervical Nerve Root Injections

    PubMed Central

    Ray, Wilson Z; Akbari, Syed; Shah, Lubdha M

    2015-01-01

    Introduction: Patients with age-related degenerative changes in the cervical spine leading to cervical spondylosis may be symptomatic or asymptomatic. Older patients with radicular pain tend to have a better response to epidural steroid injections, but it is often difficult to predict which patients will have a positive response to selective nerve root block (SNRB). We analyzed whether the cervical neuroforaminal area measured on MRI predicts immediate therapeutic responses to SNRB in patients who have cervical radiculopathy. Methods: We retrospectively reviewed all patients who had cervical SNRBs treated at a single tertiary referral center. We recorded patient demographics, the neuroforaminal area of the symptomatic and contralateral sides, Visual Analog Scale (VAS) score pre- and post-injection, history of previous cervical surgery, comorbidities, and history of tobacco use. Results: Sixty-four patients with symptoms of cervical radiculopathy treated with neuroforaminal nerve root injections had appropriate imaging and VAS scores recorded. The average foraminal area of the symptomatic side before treatment was significantly smaller than the contralateral asymptomatic neuroforamen (p<0.0001). Those patients with the smallest neuroforamen had a positive response to SNRB. Diabetes and tobacco use did not influence patient response to treatment. Conclusions: Measurement of neuroforaminal areas on MRI may represent a useful pre-procedural technique to predict which patients with symptoms of cervical radiculopathy secondary to foraminal stenosis are likely to respond to selective nerve root injections. The predictive ability appears to be limited to those patients with severe stenosis and was less useful in those patients with moderate or mild stenosis. PMID:26203404

  2. Sector computed tomographic spine scanning in the diagnosis of lumbar nerve root entrapment

    SciTech Connect

    Risius, B.; Modic, M.T.; Hardy, R.W. Jr.; Duchesneau, P.M.; Weinstein, M.A.

    1982-04-01

    The diagnosis of lumbar nerve root entrapment was made by sector computed tomography (CT) scanning in 25 patients whose myelograms were normal at the site of the CT scan abnormalities. Sector CT scanning demonstrates preoperatively which neural foramina are narrow. This information, correlated with the patient's history and physical examination, indicates which foramina should be operated on and prevents unnecessary exploration of normal neutral foramina. CT findings were confirmed surgically in 14 patients. Eleven of these 14 patients had excellent postoperative results and remain pain free.

  3. Dorsal root ganglion myeloid zinc finger protein 1 contributes to neuropathic pain after peripheral nerve trauma

    PubMed Central

    Liang, Lingli; Cao, Jing; Lutz, Brianna Marie; Bekker, Alex; Zhang, Wei; Tao, Yuan-Xiang

    2015-01-01

    Peripheral nerve injury-induced changes in gene transcription and translation in primary sensory neurons of the dorsal root ganglion (DRG) are considered to contribute to neuropathic pain genesis. Transcription factors control gene expression. Peripheral nerve injury increases the expression of myeloid zinc finger protein 1 (MZF1), a transcription factor, and promotes its binding to the voltage-gated potassium 1.2 (Kv1.2) antisense RNA gene in the injured DRG. However, whether DRG MZF1 participates in neuropathic pain is still unknown. Here, we report that blocking the nerve injury-induced increase of DRG MZF1 through microinjection of MZF1 siRNA into the injured DRG attenuated the initiation and maintenance of mechanical, cold, and thermal pain hypersensitivities in rats with chronic constriction injury (CCI) of the sciatic nerve, without affecting locomotor functions and basal responses to acute mechanical, heat, and cold stimuli. Mimicking the nerve injury-induced increase of DRG MZF1 through microinjection of recombinant adeno-associated virus 5 expressing full-length MZF1 into the DRG produced significant mechanical, cold, and thermal pain hypersensitivities in naïve rats. Mechanistically, MZF1 participated in CCI-induced reductions in Kv1.2 mRNA and protein and total Kv current and the CCI-induced increase in neuronal excitability through MZF1-triggered Kv1.2 antisense RNA expression in the injured DRG neurons. MZF1 is likely an endogenous trigger of neuropathic pain and might serve as a potential target for preventing and treating this disorder. PMID:25630025

  4. Headache in patients with cervical radiculopathy: a prospective study with selective nerve root blocks in 275 patients

    PubMed Central

    Carlsson, Jane Y.; Anderberg, Leif

    2006-01-01

    Since many years we routinely use diagnostic selective nerve root blocks (SNRB) at our department when evaluating patients with cervical radiculopathy. Frequently patients who also presented with headache reported that the headache disappeared when the nerve root responsible for the radicular pain was blocked with local anaesthetics. Headache has been described as a companioning symptom related to cervical radiculopathy but has never before been evaluated with SNRB performed in the lower cervical spine. For this reason we added to our routine an evaluation of the response from the SNRB on headache in patients with cervical radiculopathy. The aim was to describe the frequency of headache in patients with cervical radiculopathy and its response to a selective nerve root block of the nerve root/roots responsible for the radiculopathy. Can nerve root compression in the lower cervical spine produce headache? In this consecutive series of 275 patients with cervical radiculopathy, 161 patients reported that they also suffered from daily or recurrent headache located most often unilaterally on the same side as the radiculopathy. All patients underwent a careful clinical examination by a neurosurgeon and a MRI of the cervical spine. The significantly compressed root/roots, according to the MRI, underwent SNRB with a local anaesthetic. The effect of the nerve root block on the radiculopathy and the headache was carefully noted and evaluated by a physiotherapist using visual analogue scales (VAS) before and after the SNRB. All patients with headache had tender points in the neck/shoulder region on the affected side. Patients with headache graded significantly more limitations in daily activities and higher pain intensity in the neck/shoulder/arm than patients without headache. After selective nerve root block, 59% of the patients with headache reported 50% or more reduction of headache and of these 69% reported total relief. A significant correlation was seen between reduced

  5. Cervical nerve root decompression by lateral approach as salvage operation after failed anterior transdiscal surgery: technical case report

    PubMed Central

    George, Bernard

    2009-01-01

    Cervical nerve root compression caused by disco-osteophytic changes is classically operated by anterior transdiscal approach with disc replacement. If compression persists or recurs, reoperation via the same surgical route may be difficult, because of scar tissue and/or implants. An alternative approach may be necessary. We recommend the lateral cervical approach (retrojugular) as salvage operation in such cases. We report a patient with cervical nerve root compression operated by anterior transdiscal approach with plate and bone graft. As some compression persisted clinically and radiologically, the patient was re-operated via a lateral approach. The surgical access was free of scar tissue. The arthrodesis could be left intact and did not prevent effective nerve root decompression. The patient became asymptomatic. The lateral cervical approach (retrojugular) as reported here, is an excellent alternative pathway if reoperation after anterior transdiscal surgery with disc replacement becomes necessary. PMID:19449041

  6. Extrachromosomal DNA of pea (Pisum sativum) root-tip cells replicates by strand displacement

    SciTech Connect

    Krimer, D.B.; Van't Hof, J.

    1983-04-01

    In cultured pea roots there is extrachromosomal DNA associated with cells that differentiate from the G/sub 2/ phase of the cell cycle that is absent from those that differentiate from the G/sub 1/ phase. The authors examined this extrachromosomal DNA by electron microscopy and found that it consisted of three types: (i) double-stranded linear molecules with single-stranded branches (74%), (ii) double-stranded molecules without branches (26%), and (iii) free single-stranded molecules. The double-stranded molecules with or without branches were similar in length, having a modal length of 10-15 ..mu..m. The free single-stranded molecules were shorter and had a mean length of 3.8 ..mu..m. The length of the branches attached to the duplex molecules was only slightly less than that of the free form. The duplex molecules with branches were interpreted as configurations reflecting an ongoing strand-displacement process that results in free single-stranded molecules. Finally, measurements on duplex molecules with multiple branches suggested that the extrachromosomal DNA may exist in the form of tandemly repeated sequences. 8 references, 8 figures.

  7. GRAVI-2 space experiment: investigating statoliths displacement and location effects on early stages of gravity perception pathways in lentil roots.

    NASA Astrophysics Data System (ADS)

    Bizet, François; Eche, Brigitte; Pereda Loth, Veronica; Badel, Eric; Legue, Valerie; Brunel, Nicole; Label, Philippe; Gérard, Joëlle

    2016-07-01

    The plants ability to orient their growth with respect to external stimuli such as gravity is a key factor for survival and acclimation to their environment. Belowground, plant roots modulate their growth towards gravity, allowing soil exploration and uptake of water and nutrients. In roots, gravity sensing cells called statocytes are located in the center of the root cap. Statocytes contain starch-filled plastids denser than the cytoplasm, which sedimentation along the direction of gravity is widely accepted as being involved into early stages of gravity perception (the starch-statolith hypothesis; Sack, 1991). Root gravitropism following statoliths displacement is based on auxin redistribution in the root apex, inducing differential growth between the root upward and downward sides. However at the cell scale, the chain of transduction starting from statoliths displacement and leading to auxin redistribution remains poorly documented. Signaling molecules such as calcium, reactive oxygen species, nitric oxide and inositol 1,4,5-triphosphate are serious candidates previously shown to be involved within minutes before modification of the expression of auxin-related genes (Morita, 2010; Sato et al., 2015). Here, we observe and quantify statoliths displacements and locations at various levels of gravity to investigate two hypothesis: (i) Are contacts between statoliths and the endoplasmic reticulum necessary to induce gravitropism? (ii) Are very low displacements of statoliths sufficient to initiate transduction pathways such as the calcium's one? These questionings have led to an experiment called GRAVI-2 which took place aboard the ISS in 2014. During the experiment, lentil roots were grown in the European modular cultivation system for several hours in microgravity and were then submitted to short high gravity stimulus (5 and 15 minutes at 2 g) before the return to Earth for analyses. Ongoing cytological measurements will reveal the effects of statoliths

  8. The effect of tendon excursion velocity on longitudinal median nerve displacement: differences between carpal tunnel syndrome patients and controls.

    PubMed

    Filius, Anika; Thoreson, Andrew R; Wang, Yuexiang; Passe, Sandra M; Zhao, Chunfeng; An, Kai-Nan; Amadio, Peter C

    2015-04-01

    The subsynovial connective tissue (SSCT) is a viscoelastic structure connecting the median nerve (MN) and the flexor tendons in the carpal tunnel. Increased strain rates increases stiffness in viscoelastic tissues, and thereby its capacity to transfer shear load. Therefore, tendon excursion velocity may impact the MN displacement. In carpal tunnel syndrome (CTS) the SSCT is fibrotic and may be ruptured, and this may affect MN motion. In this study, ultrasonography was performed on 14 wrists of healthy controls and 25 wrists of CTS patients during controlled finger motions performed at three different velocities. Longitudinal MN and tendon excursion were assessed using a custom speckle tracking algorithm and compared across the three different velocities. CTS patients exhibited significantly less MN motion than controls (p ≤ 0.002). While in general, MN displacement increased with increasing tendon excursion velocity (p ≤ 0.031). These findings are consistent with current knowledge of SSCT mechanics in CTS, in which in some patients the fibrotic SSCT appears to have ruptured from the tendon surface. PMID:25640903

  9. [Electrophysiologic analysis of the lumbosacral radiculopathy using nerve root conduction velocity (NRCV) and cauda equina action potentials (CEAP)].

    PubMed

    Kamitani, K; Baba, H; Shimada, T; Chiba, H

    1993-07-01

    Nerve root conduction velocity (NRCV) and cauda equina action potential (CEAP) have been measured to assess the severity of lumbosacral radiculopathy, the level-specific diagnosis of the symptomatic roots, and to predict the outcome. This study included 71 patients (40 males, 31 females, average age of 54 years at the time of surgery) who underwent decompressive surgery for lumbar radiculopathy. The NRCV and CEAP were directly measured during the operation. The NRCV decreased significantly with progression of radicular symptoms. The NRCV showed a marked reduction in the nerve roots of the patients with a two years or longer history of radicular symptoms; or those with compression of the nerve roots on the imaging examinations; or nerve roots that were considered to have been subjected to persistent compression over a prolonged period with severe inflammation and adhesions. Multivariative analyses suggested that the NRCV correlated closely to the postoperative neurologic recovery, and the outcome of the lumbosacral radiculopathy could be predicted to some extent by measurements of NRCV. The level-specific diagnosis of the radiculopathy could be determined when the CEAP showed a more than 30% left-right potentials difference. PMID:8409633

  10. Generation of New Neurons in Dorsal Root Ganglia in Adult Rats after Peripheral Nerve Crush Injury

    PubMed Central

    2015-01-01

    The evidence of neurons generated ex novo in sensory ganglia of adult animals is still debated. In the present study, we investigated, using high resolution light microscopy and stereological analysis, the changes in the number of neurons in dorsal root ganglia after 30 days from a crush lesion of the rat brachial plexus terminal branches. Results showed, as expected, a relevant hypertrophy of dorsal root ganglion neurons. In addition, we reported, for the first time in the literature, that neuronal hypertrophy was accompanied by massive neuronal hyperplasia leading to a 42% increase of the number of primary sensory neurons. Moreover, ultrastructural analyses on sensory neurons showed that there was not a relevant neuronal loss as a consequence of the nerve injury. The evidence of BrdU-immunopositive neurons and neural progenitors labeled with Ki67, nanog, nestin, and sox-2 confirmed the stereological evidence of posttraumatic neurogenesis in dorsal root ganglia. Analysis of morphological changes following axonal damage in addition to immunofluorescence characterization of cell phenotype suggested that the neuronal precursors which give rise to the newly generated neurons could be represented by satellite glial cells that actively proliferate after the lesion and are able to differentiate toward the neuronal lineage. PMID:25722894

  11. Macrophages related to leptomeninges and ventral nerve roots. An ultrastructural study.

    PubMed Central

    Fraher, J P; McDougall, R D

    1975-01-01

    In immature rats active macrophages were frequently seen projecting into the subarachnoid space from the surface of the leptomeninges. They also occurred between the layers of the pia and within the nerve roots. They were most frequent during the first two weeks after birth, which is a period of rapid neural growth and myelination in ventral roots. In contrast, they were much fewer at later stages. The ultrastructural characteristics of these cells are described. It is suggested that these cells take part in tissue growth and remodelling by the removal of material which degenerates or becomes redundant during development. For example, they may ingest effete leptomeningeal cells or fragments of them. Those within the ventral roots may phagocytose abnormal Schwann cells, or the myelin of sheaths which have failed to develop normally. It is also suggested that macrophages may be involved in the excavation of the subarachnoid space. Another possible function in which they may be involved is the ingestion of material, possibly of a protein nature, from the cerebrospinal fluid. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:1213953

  12. Antral bony wall erosion, trigeminal nerve injury, and enophthalmos after root canal surgery

    PubMed Central

    Ferreira, Eduardo; Antunes, Luís; Dinis, Paulo Borges

    2016-01-01

    Introduction: The frequently used irrigant in dental surgery, sodium hypochlorite, is occasionally the cause of minor, usually circumscribed, adverse effects. Severe, extensive complications, with lasting sequelae, however, also can occur, as in the case we report herein. Case Report: A 55-year-old woman underwent an endodontic procedure on a maxillary molar, whose roots, unknown to the surgeon, were protruding into the maxillary sinus. After sodium hypochlorite root canal irrigation, the patient immediately developed intense facial pain, facial edema, and periorbital cellulitis. An emergency department evaluation diagnosed an intense inflammatory disease of the maxillary sinus, with significant destruction of its bony walls, accompanied by midface paraesthesia due to infraorbital nerve injury. In the following weeks, the patient slowly developed enophthalmos due to bone erosion of the orbit floor. Treatment, besides prolonged oral steroids, required the endoscopic endonasal opening of the maxillary sinus for profuse irrigation. Two years later, the patient maintained a complete loss of function of the maxillary sinus, anesthesia-paraesthesia of the midface, and inferior dystonia of the eye with an enophthalmos. Conclusion: Dentists, maxillofacial surgeons, and otorhinolaryngologists should all be aware of the whole spectrum of complications of even the simplest dental work. Sodium hypochlorite irrigations should be used cautiously in root canal surgery, with the full awareness of its potential for causing soft-tissue damage. PMID:27465790

  13. Confocal imaging reveals three-dimensional fine structure difference between ventral and dorsal nerve roots

    NASA Astrophysics Data System (ADS)

    Wu, Yuxiang; Sui, Tao; Cao, Xiaojian; Lv, Xiaohua; Zeng, Shaoqun; Sun, Peng

    2011-05-01

    Peripheral nerve injury repair is one of the most challenging problems in neurosurgery, partially due to lack of knowledge of three-dimensional (3-D) fine structure and organization of peripheral nerves. In this paper, we explored the structures of nerve fibers in ventral and dorsal nerves with a laser scanning confocal microscopy. Thick tissue staining results suggested that nerve fibers have a different 3-D structure in ventral and dorsal nerves, and reconstruction from serial sectioning images showed that in ventral nerves the nerve fibers travel in a winding form, while in dorsal nerves, the nerve fibers form in a parallel cable pattern. These structural differences could help surgeons to differentiate ventral and dorsal nerves in peripheral nerve injury repair, and also facilitate scientists to get a deeper understanding about nerve fiber organization.

  14. More nerve root injuries occur with minimally invasive lumbar surgery, especially extreme lateral interbody fusion: A review

    PubMed Central

    Epstein, Nancy E.

    2016-01-01

    Background: In the lumbar spine, do more nerve root injuries occur utilizing minimally invasive surgery (MIS) techniques versus open lumbar procedures? To answer this question, we compared the frequency of nerve root injuries for multiple open versus MIS operations including diskectomy, laminectomy with/without fusion addressing degenerative disc disease, stenosis, and/or degenerative spondylolisthesis. Methods: Several of Desai et al. large Spine Patient Outcomes Research Trial studies showed the frequency for nerve root injury following an open diskectomy ranged from 0.13% to 0.25%, for open laminectomy/stenosis with/without fusion it was 0%, and for open laminectomy/stenosis/degenerative spondylolisthesis with/without fusion it was 2%. Results: Alternatively, one study compared the incidence of root injuries utilizing MIS transforaminal lumbar interbody fusion (TLIF) versus posterior lumbar interbody fusion (PLIF) techniques; 7.8% of PLIF versus 2% of TLIF patients sustained root injuries. Furthermore, even higher frequencies of radiculitis and nerve root injuries occurred during anterior lumbar interbody fusions (ALIFs) versus extreme lateral interbody fusions (XLIFs). These high frequencies were far from acceptable; 15.8% following ALIF experienced postoperative radiculitis, while 23.8% undergoing XLIF sustained root/plexus deficits. Conclusions: This review indicates that MIS (TLIF/PLIF/ALIF/XLIF) lumbar surgery resulted in a higher incidence of root injuries, radiculitis, or plexopathy versus open lumbar surgical techniques. Furthermore, even a cursory look at the XLIF data demonstrated the greater danger posed to neural tissue by this newest addition to the MIS lumbar surgical armamentariu. The latter should prompt us as spine surgeons to question why the XLIF procedure is still being offered to our patients? PMID:26904372

  15. The Accuracy of the Physical Examination for the Diagnosis of Midlumbar and Low Lumbar Nerve Root Impingement

    PubMed Central

    Suri, Pradeep; Rainville, James; Katz, Jeffrey N.; Jouve, Cristin; Hartigan, Carol; Limke, Janet; Pena, Enrique; Li, Ling; Swaim, Bryan; Hunter, David J

    2010-01-01

    Study Design Cross-sectional study with prospective recruitment. Objective To determine the accuracy of the physical examination for the diagnosis of midlumbar nerve root impingement (L2, L3, or L4), low lumbar nerve root impingement (L5 or S1) and level-specific lumbar nerve root impingement on magnetic resonance imaging (MRI), using individual tests and combinations of tests. Summary of Background Data The sensitivity and specificity of the physical examination for the localization of nerve root impingement has not been previously studied. Methods Sensitivities, specificities and LRs were calculated for the ability of individual tests and test combinations to predict the presence or absence of nerve root impingement at midlumbar, low lumbar, and specific nerve root levels. Results LRs ≥5.0 indicate moderate to large changes from pre-test probability of nerve root impingement to post-test probability. For the diagnosis of midlumbar impingement, the femoral stretch test (FST), crossed femoral stretch test (CFST), medial ankle pinprick sensation, and patellar reflex testing demonstrated LRs ≥5.0 (LR ∞). LRs ≥5.0 were seen with the combinations of FST and either patellar reflex testing (LR 7.0; 95% CI 2.3–21), or the sit-to-stand test (LR ∞). For the diagnosis of low lumbar impingement, the Achilles reflex test demonstrated a LR ≥5.0 (LR 7.1; CI 0.96–53); test combinations did not increase LRs. For the diagnosis of level-specific impingement, LRs ≥5.0 were seen for anterior thigh sensation at L2 (LR 13; 95% CI 1.8–87); FST at L3 (LR 5.7 ; 95% CI 2.3–4.4); patellar reflex testing (LR 7.7; 95% CI 1.7–35), medial ankle sensation (LR ∞), or CFST (LR 13; 95% CI 1.8–87) at L4; and hip abductor strength at L5(LR 11; 95% CI 1.3–84). Test combinations increased LRs for level-specific root impingement at the L4 level only. Conclusions Individual physical examination tests may provide clinical information which substantially alters the likelihood

  16. Cells of origin in the embryonic nerve roots for NF1-associated plexiform neurofibroma.

    PubMed

    Chen, Zhiguo; Liu, Chiachi; Patel, Amish J; Liao, Chung-Ping; Wang, Yong; Le, Lu Q

    2014-11-10

    Neurofibromatosis type 1 is a tumor-predisposing genetic disorder. Plexiform neurofibromas are common NF1 tumors carrying a risk of malignant transformation, which is typically fatal. Little is known about mechanisms mediating initiation and identity of specific cell type that gives rise to neurofibromas. Using cell-lineage tracing, we identify a population of GAP43(+) PLP(+) precursors in embryonic nerve roots as the cells of origin for these tumors and report a non-germline neurofibroma model for preclinical drug screening to identify effective therapies. The identity of the tumor cell of origin and facility for isolation and expansion provides fertile ground for continued analysis to define factors critical for neurofibromagenesis. It also provides unique approaches to develop therapies to prevent neurofibroma formation in NF1 patients. PMID:25446898

  17. Ventral root re-implantation is better than peripheral nerve transplantation for motoneuron survival and regeneration after spinal root avulsion injury

    PubMed Central

    2013-01-01

    Background Peripheral nerve (PN) transplantation and ventral root implantation are the two common types of recovery operations to restore the connection between motoneurons and their target muscles after brachial plexus injury. Despite experience accumulated over the past decade, fundamental knowledge is still lacking concerning the efficacy of the two microsurgical interventions. Methods Thirty-eight adult female Sprague–Dawley rats were divided into 5 groups. Immediately following root avulsion, animals in the first group (n = 8) and the second group (n = 8) received PN graft and ventral root implantation respectively. The third group (n = 8) and the fourth group (n = 8) received PN graft and ventral root implantation respectively at one week after root avulsion. The fifth group received root avulsion only as control (n = 6). The survival and axonal regeneration of severed motoneurons were investigated at 6 weeks post-implantation. Results Re-implantation of ventral roots, both immediately after root avulsion and in delay, significantly increased the survival and regeneration of motoneurons in the avulsed segment of the spinal cord as compared with PN graft transplantation. Conclusions The ventral root re-implantation is a better surgical repairing procedure than PN graft transplantation for brachial plexus injury because of its easier manipulation for re-implanting avulsed ventral roots to the preferred site, less possibility of causing additional damage and better effects on motoneuron survival and axonal regeneration. PMID:23799915

  18. The comparative performance of Roots type aircraft engine superchargers as affected by change in impeller speed and displacement

    NASA Technical Reports Server (NTRS)

    Ware, Marsden; Wilson, Ernest E

    1929-01-01

    This report presents the results of tests made on three sizes of roots type aircraft engine superchargers. The impeller contours and diameters of these machines were the same, but the length were 11, 8 1/4, and 4 inches, giving displacements of 0.509, 0.382, and 0.185 cubic foot per impeller revolution. The information obtained serves as a basis for the examination of the individual effects of impeller speed and displacement on performance and of the comparative performance when speed and displacement are altered simultaneously to meet definite service requirements. According to simple theory, when assuming no losses, the air weight handled and the power required for a given pressure difference are directly proportional to the speed and the displacement. These simple relations are altered considerably by the losses. When comparing the performance of different sizes of machines whose impeller speeds are so related that the same service requirements are met, it is found that the individual effects of speed and displacement are canceled to a large extent, and the only considerable difference is the difference in the power losses which decrease with increase in the displacement and the accompanying decrease in speed. This difference is small in relation to the net power of the engine supercharger unit, so that a supercharger with short impellers may be used in those applications where the space available is very limited with any considerable sacrifice in performance.

  19. Time Course of Substance P Expression in Dorsal Root Ganglia Following Complete Spinal Nerve Transection

    PubMed Central

    Weissner, Wendy; Winterson, Barbara J.; Stuart-Tilley, Alan; Devor, Marshall; Bove, Geoffrey M.

    2008-01-01

    Recent evidence suggests that substance P (SP) is upregulated in primary sensory neurons following axotomy, and that this change occurs in larger neurons that do not usually produce SP. If so, this upregulation may allow normally neighboring, uninjured, and non-nociceptive dorsal root ganglion (DRG) neurons to become effective in activating pain pathways. Using immunohistochemistry, we performed a unilateral L5 spinal nerve transection upon male Wistar rats, and measured SP expression in ipsilateral L4 and L5 DRGs and contralateral L5 DRGs, at 1 to 14 days postoperatively (dpo), and in control and sham operated rats. In normal and sham operated DRGs, SP was detectable almost exclusively in small neurons (≤ 800 μm2). Following surgery, the mean size of SP-positive neurons from the axotomized L5 ganglia was greater at 2, 4, 7 and 14 dpo. Among large neurons (> 800 μm2) from the axotomized L5, the percentage of SP-positive neurons increased at 2, 4, 7, and 14 dpo. Among small neurons from the axotomized L5, the percentage of SP-positive neurons was increased at 1 and 3 dpo, but was decreased at 7 and 14 dpo. Thus, SP expression is affected by axonal damage, and the time course of the expression is different between large and small DRG neurons. These data support a role of SP-producing, large DRG neurons in persistent sensory changes due to nerve injury. PMID:16680762

  20. Computerized tomography myelography with coronal and oblique coronal view for diagnosis of nerve root avulsion in brachial plexus injury

    PubMed Central

    2007-01-01

    Background The authors describe a new computerized tomography (CT) myelography technique with coronal and oblique coronal view to demonstrate the status of the cervical nerve rootlets involved in brachial plexus injury. They discuss the value of this technique for diagnosis of nerve root avulsion compared with CT myelography with axial view. Methods CT myelography was performed with penetration of the cervical subarachnoid space by the contrast medium. Then the coronal and oblique coronal reconstructions were created. The results of CT myelography were evaluated and classified with presence of pseudomeningocele, intradural ventral nerve rootlets, and intradural dorsal nerve rootlets. The diagnosis was by extraspinal surgical exploration with or without spinal evoked potential measurements and choline acetyl transferase activity measurement in 25 patients and recovery by a natural course in 3 patients. Its diagnostic accuracy was compared with that of CT myelography with axial view, correlated with surgical findings or a natural course in 57 cervical roots in 28 patients. Results Coronal and oblique coronal views were superior to axial views in visualization of the rootlets and orientation of the exact level of the root. Sensitivity and specificity for coronal and oblique coronal views of unrecognition of intradural ventral and dorsal nerve root shadow without pseudomeningocele in determining pre-ganglionic injury were 100% and 96%, respectively. There was no statistically significant difference between coronal and oblique coronal views and axial views. Conclusion The information by the coronal and oblique coronal slice CT myelography enabled the authors to assess the rootlets of the brachial plexus and provided valuable data for helping to decide whether to proceed with exploration, nerve repair, primary reconstruction. PMID:17651476

  1. Multidimensional ultrasound imaging of the wrist: Changes of shape and displacement of the median nerve and tendons in carpal tunnel syndrome.

    PubMed

    Filius, Anika; Scheltens, Marjan; Bosch, Hans G; van Doorn, Pieter A; Stam, Henk J; Hovius, Steven E R; Amadio, Peter C; Selles, Ruud W

    2015-09-01

    Dynamics of structures within the carpal tunnel may alter in carpal tunnel syndrome (CTS) due to fibrotic changes and increased carpal tunnel pressure. Ultrasound can visualize these potential changes, making ultrasound potentially an accurate diagnostic tool. To study this, we imaged the carpal tunnel of 113 patients and 42 controls. CTS severity was classified according to validated clinical and nerve conduction study (NCS) classifications. Transversal and longitudinal displacement and shape (changes) were calculated for the median nerve, tendons and surrounding tissue. To predict diagnostic value binary logistic regression modeling was applied. Reduced longitudinal nerve displacement (p≤ 0.019), increased nerve cross-sectional area (p≤ 0.006) and perimeter (p≤ 0.007), and a trend of relatively changed tendon displacements were seen in patients. Changes were more convincing when CTS was classified as more severe. Binary logistic modeling to diagnose CTS using ultrasound showed a sensitivity of 70-71% and specificity of 80-84%. In conclusion, CTS patients have altered dynamics of structures within the carpal tunnel. PMID:25865180

  2. Charcot-Marie-Tooth syndrome and neurofibromatosis type 1 with multiple neurofibromas of the entire spinal nerve roots

    PubMed Central

    Onu, David O; Hunn, Andrew W; Peters-Willke, Jens

    2013-01-01

    The coexistence of polyneuropathy which has the definite clinical and electromyographical findings consistent with Charcot-Marie-Tooth (CMT) syndrome and neurofibromatosis type 1 (NF1) has infrequently been reported. We describe a patient with both CMT and NF1, who had multiple neurofibromas involving the entire spinal neural axis. In addition, he had multiple neurofibromas distributed within the ileopsoas and gluteus muscles and subcutaneous tissues. These lesions were detected readily by MRI and the patient underwent successful surgical resection of the largest tumours compressing bilateral C2 nerve roots. To our knowledge, this is the first reported case of CMT syndrome coexisting with NF1 in which multiple neurofibromas involved the entire spinal nerve roots. We discuss the diagnostic and therapeutic challenges, emphasising the role of MRI and electrophysiology in such cases and provide a literature review. PMID:23853192

  3. Charcot-Marie-Tooth syndrome and neurofibromatosis type 1 with multiple neurofibromas of the entire spinal nerve roots.

    PubMed

    Onu, David O; Hunn, Andrew W; Peters-Willke, Jens

    2013-01-01

    The coexistence of polyneuropathy which has the definite clinical and electromyographical findings consistent with Charcot-Marie-Tooth (CMT) syndrome and neurofibromatosis type 1 (NF1) has infrequently been reported. We describe a patient with both CMT and NF1, who had multiple neurofibromas involving the entire spinal neural axis. In addition, he had multiple neurofibromas distributed within the ileopsoas and gluteus muscles and subcutaneous tissues. These lesions were detected readily by MRI and the patient underwent successful surgical resection of the largest tumours compressing bilateral C2 nerve roots. To our knowledge, this is the first reported case of CMT syndrome coexisting with NF1 in which multiple neurofibromas involved the entire spinal nerve roots. We discuss the diagnostic and therapeutic challenges, emphasising the role of MRI and electrophysiology in such cases and provide a literature review. PMID:23853192

  4. [Teflon granuloma after microvascular decompression of the trigeminal nerve root in a patient with recurrent trigeminal neuralgia].

    PubMed

    Rzaev, D A; Kulikova, E V; Moysak, G I; Voronina, E I; Ageeva, T A

    2016-01-01

    The use of a Teflon implant for Jannetta surgery in patients with trigeminal neuralgia is complicated in rare cases by the development of a Teflon granuloma and can cause recurrent facial pain. The article presents a clinical case of a Teflon granuloma developed after microvascular decompression of the trigeminal nerve root, describes the surgical findings and histological picture, and analyzes the literature, causes of granuloma development, and recommendations for treatment of these patients. PMID:27070261

  5. Oxygen-Ozone Therapy for Herniated Lumbar Disc in Patients with Subacute Partial Motor Weakness Due to Nerve Root Compression

    PubMed Central

    Dall'Olio, Massimo; Princiotta, Ciro; Cirillo, Luigi; Budai, Caterina; de Santis, Fabio; Bartolini, Stefano; Serchi, Elena; Leonardi, Marco

    2014-01-01

    Summary Intradiscal oxygen-ozone (O2-O3) chemonucleolysis is a well-known effective treatment for pain caused by protruding disc disease and nerve root compression due to bulging or herniated disc. The most widely used therapeutic combination is intradiscal injection of an O2-O3 mixture (chemonucleolysis), followed by periradicular injection of O2-O3, steroid and local anaesthetic to enhance the anti-inflammatory and analgesic effect. The treatment is designed to resolve pain and is administered to patients without motor weakness, whereas patients with acute paralysis caused by nerve root compression undergo surgery 24-48h after the onset of neurological deficit. This paper reports on the efficacy of O2-O3 chemonucleolysis associated with anti-inflammatory foraminal injection in 13 patients with low back pain and cruralgia, low back pain and sciatica and subacute partial motor weakness caused by nerve root compression unresponsive to medical treatment. All patients were managed in conjunction with our colleagues in the Neurosurgery Unit of Bellaria Hospital and the IRCCS Institute of Neurological Sciences, Bologna. The outcomes obtained are promising: 100% patients had a resolution of motor weakness, while 84.6% had complete pain relief. Our results demonstrate that O2-O3 therapy can be considered a valid treatment option for this category of patients. PMID:25363257

  6. Blood-nerve barrier: distribution of anionic sites on the endothelial plasma membrane and basal lamina of dorsal root ganglia.

    PubMed

    Bush, M S; Reid, A R; Allt, G

    1991-09-01

    Previous investigations of the blood-nerve barrier have correlated the greater permeability of ganglionic endoneurial vessels, compared to those of nerve trunks, with the presence of fenestrations and open intercellular junctions. Recent studies have demonstrated reduced endothelial cell surface charge in blood vessels showing greater permeability. To determine the distribution of anionic sites on the plasma membranes and basal laminae of endothelial cells in dorsal root ganglia, cationic colloidal gold and cationic ferritin were used. Electron microscopy revealed the existence of endothelial microdomains with differing labelling densities. Labelling indicated that caveolar and fenestral diaphragms and basal laminae are highly anionic at physiological pH, luminal plasma membranes and endothelial processes are moderately charged and abluminal plasma membranes are weakly anionic. Tracers did not occur in caveolae or cytoplasmic vesicles. In vitro tracer experiments at pH values of 7.3, 5.0, 3.5 and 2.0 indicated that the anionic charge on the various endothelial domains was contributed by chemical groups with differing pKa values. In summary, the labelling of ganglionic and sciatic nerve vessels was similar except for the heavy labelling of diaphragms in a minority of endoneurial vessels in ganglia. This difference is likely to account in part for the greater permeability of ganglionic endoneurial vessels. The results are discussed with regard to the blood-nerve and -brain barriers and vascular permeability in other tissues and a comparison made between the ultrastructure and anionic microdomains of epi-, peri- and endoneurial vessels of dorsal root ganglia and sciatic nerves. PMID:1960538

  7. The Influence of Random Element Displacement on DOA Estimates Obtained with (Khatri–Rao-)Root-MUSIC

    PubMed Central

    Inghelbrecht, Veronique; Verhaevert, Jo; van Hecke, Tanja; Rogier, Hendrik

    2014-01-01

    Although a wide range of direction of arrival (DOA) estimation algorithms has been described for a diverse range of array configurations, no specific stochastic analysis framework has been established to assess the probability density function of the error on DOA estimates due to random errors in the array geometry. Therefore, we propose a stochastic collocation method that relies on a generalized polynomial chaos expansion to connect the statistical distribution of random position errors to the resulting distribution of the DOA estimates. We apply this technique to the conventional root-MUSIC and the Khatri-Rao-root-MUSIC methods. According to Monte-Carlo simulations, this novel approach yields a speedup by a factor of more than 100 in terms of CPU-time for a one-dimensional case and by a factor of 56 for a two-dimensional case. PMID:25393783

  8. The influence of random element displacement on DOA estimates obtained with (Khatri-Rao-)root-MUSIC.

    PubMed

    Inghelbrecht, Veronique; Verhaevert, Jo; van Hecke, Tanja; Rogier, Hendrik

    2014-01-01

    Although a wide range of direction of arrival (DOA) estimation algorithms has been described for a diverse range of array configurations, no specific stochastic analysis framework has been established to assess the probability density function of the error on DOA estimates due to random errors in the array geometry. Therefore, we propose a stochastic collocation method that relies on a generalized polynomial chaos expansion to connect the statistical distribution of random position errors to the resulting distribution of the DOA estimates. We apply this technique to the conventional root-MUSIC and the Khatri-Rao-root-MUSIC methods. According to Monte-Carlo simulations, this novel approach yields a speedup by a factor of more than 100 in terms of CPU-time for a one-dimensional case and by a factor of 56 for a two-dimensional case. PMID:25393783

  9. S3 Dorsal Root Ganglion/Nerve Root Stimulation for Refractory Postsurgical Perineal Pain: Technical Aspects of Anchorless Sacral Transforaminal Lead Placement

    PubMed Central

    Zuidema, X.; Breel, J.; Wille, F.

    2016-01-01

    Chronic perineal pain limits patients in physical and sexual activities, leading to social and psychological distress. In most cases, this pain develops after surgery in the urogenital area or as a consequence of trauma. Neuromodulation is one of the options in chronic postsurgical perineal pain treatment. We present a case of refractory perineal pain after right sided surgical resection of a Bartholin's cyst which was treated with third sacral nerve root/dorsal root ganglion stimulation using the transforaminal approach. We describe a new anchorless lead placement technique using a unique curved lead delivery sheath. We postulate that this new posterior foraminal technique of lead placement is simple, safe, and reversible and may lower the occurrence of lead related complications. PMID:27123351

  10. S3 Dorsal Root Ganglion/Nerve Root Stimulation for Refractory Postsurgical Perineal Pain: Technical Aspects of Anchorless Sacral Transforaminal Lead Placement.

    PubMed

    Zuidema, X; Breel, J; Wille, F

    2016-01-01

    Chronic perineal pain limits patients in physical and sexual activities, leading to social and psychological distress. In most cases, this pain develops after surgery in the urogenital area or as a consequence of trauma. Neuromodulation is one of the options in chronic postsurgical perineal pain treatment. We present a case of refractory perineal pain after right sided surgical resection of a Bartholin's cyst which was treated with third sacral nerve root/dorsal root ganglion stimulation using the transforaminal approach. We describe a new anchorless lead placement technique using a unique curved lead delivery sheath. We postulate that this new posterior foraminal technique of lead placement is simple, safe, and reversible and may lower the occurrence of lead related complications. PMID:27123351

  11. Upregulation of EMMPRIN (OX47) in Rat Dorsal Root Ganglion Contributes to the Development of Mechanical Allodynia after Nerve Injury

    PubMed Central

    Wang, Qun; Sun, Yanyuan; Ren, Yingna; Gao, Yandong; Tian, Li; Liu, Yang; Pu, Yanan; Gou, Xingchun; Chen, Yanke; Lu, Yan

    2015-01-01

    Matrix metalloproteinases (MMPs) are widely implicated in inflammation and tissue remodeling associated with various neurodegenerative diseases and play an important role in nociception and allodynia. Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) plays a key regulatory role for MMP activities. However, the role of EMMPRIN in the development of neuropathic pain is not clear. Western blotting, real-time quantitative RT-PCR (qRT-PCR), and immunofluorescence were performed to determine the changes of messenger RNA and protein of EMMPRIN/OX47 and their cellular localization in the rat dorsal root ganglion (DRG) after nerve injury. Paw withdrawal threshold test was examined to evaluate the pain behavior in spinal nerve ligation (SNL) model. The lentivirus containing OX47 shRNA was injected into the DRG one day before SNL. The expression level of both mRNA and protein of OX47 was markedly upregulated in ipsilateral DRG after SNL. OX47 was mainly expressed in the extracellular matrix of DRG. Administration of shRNA targeted against OX47 in vivo remarkably attenuated mechanical allodynia induced by SNL. In conclusion, peripheral nerve injury induced upregulation of OX47 in the extracellular matrix of DRG. RNA interference against OX47 significantly suppressed the expression of OX47 mRNA and the development of mechanical allodynia. The altered expression of OX47 may contribute to the development of neuropathic pain after nerve injury. PMID:26697232

  12. Inhibitory Activity of Yokukansankachimpihange against Nerve Growth Factor-Induced Neurite Growth in Cultured Rat Dorsal Root Ganglion Neurons.

    PubMed

    Murayama, Chiaki; Watanabe, Shimpei; Nakamura, Motokazu; Norimoto, Hisayoshi

    2015-01-01

    Chronic pruritus is a major and distressing symptom of many cutaneous diseases, however, the treatment remains a challenge in the clinic. The traditional Chinese-Japanese medicine (Kampo medicine) is a conservative and increasingly popular approach to treat chronic pruritus for both patients and medical providers. Yokukansankachimpihange (YKH), a Kampo formula has been demonstrated to be effective in the treatment of itching of atopic dermatitis in Japan although its pharmacological mechanism is unknown clearly. In an attempt to clarify its pharmacological actions, in this study, we focused on the inhibitory activity of YKH against neurite growth induced with nerve growth factor (NGF) in cultured rat dorsal root ganglion (DRG) neurons because epidermal hyperinnervation is deeply related to itch sensitization. YKH showed approximately 200-fold inhibitory activity against NGF-induced neurite growth than that of neurotropin (positive control), a drug used clinically for treatment of chronic pruritus. Moreover, it also found that Uncaria hook, Bupleurum root and their chemical constituents rhynchophylline, hirsutine, and saikosaponin a, d showed inhibitory activities against NGF-induced neurite growth, suggesting they should mainly contribute to the inhibitory activity of YKH. Further study on the effects of YKH against epidermal nerve density in "itch-scratch" animal models is under investigation. PMID:26287150

  13. Intra-epidermal nerve fibres in human skin: back to the roots.

    PubMed

    Abels, Christoph

    2014-04-01

    Regarding the existence and the role of intra-epidermal nerve fibres, the literature is ambiguous. However, performing a literature search, a landmark paper turned up that even many dermatologists seem to have forgotten, or may not even know at all. This paper is entitled 'The innervation of human epidermis' written by Arthur and Shelley (J Invest Dermatol, 32, 1959, 397). The full text is available via http://www.nature.com/jid/journal/v32/n3/pdf/jid195969a.pdf. The authors present data on intra-epidermal nerves at 16 representative body areas. The existence of intra-epidermal nerve fibres is undisputable and does not only explain clinical symptoms but may even provide a promising target for drug development. PMID:24450967

  14. Different types of spinal afferent nerve endings in stomach and esophagus identified by anterograde tracing from dorsal root ganglia.

    PubMed

    Spencer, Nick J; Kyloh, Melinda; Beckett, Elizabeth A; Brookes, Simon; Hibberd, Tim

    2016-10-15

    In visceral organs of mammals, most noxious (painful) stimuli as well as innocuous stimuli are detected by spinal afferent neurons, whose cell bodies lie in dorsal root ganglia (DRGs). One of the major unresolved questions is the location, morphology, and neurochemistry of the nerve endings of spinal afferents that actually detect these stimuli in the viscera. In the upper gastrointestinal (GI) tract, there have been many anterograde tracing studies of vagal afferent endings, but none on spinal afferent endings. Recently, we developed a technique that now provides selective labeling of only spinal afferents. We used this approach to identify spinal afferent nerve endings in the upper GI tract of mice. Animals were anesthetized, and injections of dextran-amine were made into thoracic DRGs (T8-T12). Seven days post surgery, mice were euthanized, and the stomach and esophagus were removed, fixed, and stained for calcitonin gene-related peptide (CGRP). Spinal afferent axons were identified that ramified extensively through many rows of myenteric ganglia and formed nerve endings in discrete anatomical layers. Most commonly, intraganglionic varicose endings (IGVEs) were identified in myenteric ganglia of the stomach and varicose simple-type endings in the circular muscle and mucosa. Less commonly, nerve endings were identified in internodal strands, blood vessels, submucosal ganglia, and longitudinal muscle. In the esophagus, only IGVEs were identified in myenteric ganglia. No intraganglionic lamellar endings (IGLEs) were identified in the stomach or esophagus. We present the first identification of spinal afferent endings in the upper GI tract. Eight distinct types of spinal afferent endings were identified in the stomach, and most of them were CGRP immunoreactive. J. Comp. Neurol. 524:3064-3083, 2016. © 2016 Wiley Periodicals, Inc. PMID:27019197

  15. Atypic geniculate neuralgia: atypic anatomic correlation of cranial nerve roots and AICA.

    PubMed

    Ozer, Füsun Demirçivi; Duransoy, Yusuf Kurtuluş; Camlar, Mahmut

    2009-08-01

    Geniculate neuralgia is a rare cause of craniofacial pains. The anterior inferior cerebellar artery is the offending vessel which compress nervus intermedius in the patients with typical geniculate neuralgia. We report a patient whose pain was atypical for either geniculate neuralgia and trigeminal neuralgia. At operation the anterior inferior cerebellar artery was coursing with the nerves and was separated. After the decompression the pain resolved immediately. PMID:19404569

  16. Microsurgical procedures in the peripheral nerves and the dorsal root entry zone for the treatment of spasticity.

    PubMed

    Sindou, M; Keravel, Y

    1988-01-01

    When spasticity becomes severe and harmful, in spite of physical and medical therapy, neurosurgery can give functional improvement. This paper deals with the long term results of Selective Peripheral Neurotomies of the Tibial Nerve and Selective Posterior Rhizotomies in the Dorsal Root Entry Zone, in 123 patients with spastic disorders localized to the limbs. The micro-techniques and intra-operative electro-stimulation for identification of the nervous structures responsible for the spastic components, can give a substantial reduction of the harmful spasticity, without suppressing the useful muscle tone and impairing the residual motor and sensory functions. The results were effective, with a 1 to 13 year follow-up (5 on average), in 89% of 47 Selective Peripheral Neurotomies of the tibial nerve for spastic foot, in 92% of 53 Selective Posterior Rhizotomies for paraplegia and in 87% of 23 Selective Posterior Rhizotomies for hemiplegia. In the most severe situations ("comfort" indications), correction of the abnormal postures and relief of pain facilitated nursing and physiotherapy. Sometimes there was reappearance of some useful voluntary movements. In the less affected patients ("functional" indications), the suppression of the harmful spastic components made the persistant capacities more effective. PMID:3165206

  17. H-reflex amplitude asymmetry is an earlier sign of nerve root involvement than latency in patients with S1 radiculopathy

    PubMed Central

    2011-01-01

    Background Based on our clinical experience, the H-reflex amplitude asymmetry might be an earlier sign of nerve root involvement than latency in patients with S1 radiculopathy. However, no data to support this assumption are available. The purpose of this study was to review and report the electrophysiological changes in H-reflex amplitude and latency in patients with radiculopathy in order to determine if there is any evidence to support the assumption that H-reflex amplitude is an earlier sign of nerve root involvement than latency. Results Patients with radiculopathy showed significant amplitude asymmetry when compared with healthy controls. However, latency was not always significantly different between patients and healthy controls. These findings suggest nerve root axonal compromise that reduced reflex amplitude earlier than the latency parameter (demyelination) during the pathologic processes. Conclusion Contrary to current clinical thought, H-reflex amplitude asymmetry is an earlier sign/parameter of nerve root involvement in patients with radiculopathy compared with latency. PMID:21466665

  18. Neural-Dural Transition at the Thoracic and Lumbar Spinal Nerve Roots: A Histological Study of Human Late-Stage Fetuses

    PubMed Central

    Cho, Kwang Ho; Jin, Zhe Wu; Abe, Hiroshi; Shibata, Shunichi; Murakami, Gen; Rodríguez-Vázquez, Jose Francisco

    2016-01-01

    Epidural blocks have been used extensively in infants. However, little histological information is available on the immature neural-dural transition. The neural-dural transition was histologically investigated in 12 late-stage (28–30 weeks) fetuses. The dural sheath of the spinal cord was observed to always continue along the nerve roots with varying thicknesses between specimens and segments, while the dorsal root ganglion sheath was usually very thin or unclear. Immature neural-dural transitions were associated with effective anesthesia. The posterior radicular artery was near the dorsal root ganglion and/or embedded in the nerve root, whereas the anterior radicular artery was separated from the nearest nerve root. The anterior radicular artery was not associated with the dural sheath but with thin mesenchymal tissue. The numbers of radicular arteries tended to become smaller in larger specimens. Likewise, larger specimens of the upper thoracic and lower lumbar segments did not show the artery. Therefore, elimination of the radicular arteries to form a single artery of Adamkiewicz was occurring in late-stage fetuses. The epidural space was filled with veins, and the loose tissue space extended ventrolaterally to the subpleural tissue between the ribs. Consequently, epidural blocks in infants require special attention although immature neural-dural transitions seemed to increase the effect. PMID:27069926

  19. Neural-Dural Transition at the Thoracic and Lumbar Spinal Nerve Roots: A Histological Study of Human Late-Stage Fetuses.

    PubMed

    Cho, Kwang Ho; Jin, Zhe Wu; Abe, Hiroshi; Shibata, Shunichi; Murakami, Gen; Rodríguez-Vázquez, Jose Francisco

    2016-01-01

    Epidural blocks have been used extensively in infants. However, little histological information is available on the immature neural-dural transition. The neural-dural transition was histologically investigated in 12 late-stage (28-30 weeks) fetuses. The dural sheath of the spinal cord was observed to always continue along the nerve roots with varying thicknesses between specimens and segments, while the dorsal root ganglion sheath was usually very thin or unclear. Immature neural-dural transitions were associated with effective anesthesia. The posterior radicular artery was near the dorsal root ganglion and/or embedded in the nerve root, whereas the anterior radicular artery was separated from the nearest nerve root. The anterior radicular artery was not associated with the dural sheath but with thin mesenchymal tissue. The numbers of radicular arteries tended to become smaller in larger specimens. Likewise, larger specimens of the upper thoracic and lower lumbar segments did not show the artery. Therefore, elimination of the radicular arteries to form a single artery of Adamkiewicz was occurring in late-stage fetuses. The epidural space was filled with veins, and the loose tissue space extended ventrolaterally to the subpleural tissue between the ribs. Consequently, epidural blocks in infants require special attention although immature neural-dural transitions seemed to increase the effect. PMID:27069926

  20. Translaminar Microendoscopic Herniotomy for Cranially Migrated Lumbar Disc Herniations Encroaching on the Exiting Nerve Root in the Preforaminal and Foraminal Zones

    PubMed Central

    Tono, Osamu; Senba, Hideyuki; Kitamura, Takahiro; Komiya, Norihiro; Oga, Masayoshi; Shidahara, Satoshi

    2013-01-01

    Study Design Case series. Purpose The aim of this study was to describe translaminar microendoscopic herniotomy (TL-MEH) for cranially migrated lumbar disc herniations encroaching on the exiting nerve root in the preforaminal and foraminal zones and to report preliminary results of the procedure. Overview of Literature Conventional interlaminar approaches for preforaminal and foraminal lumbar disc herniations result in extensive removal of the lamina and facet joint to remove disc fragments safely. More destructive approaches increase the risk of postoperative segmental instability. Methods TL-MEH is a minimally invasive procedure for herniotomy via the translaminar approach using a microendoscopic technique. TL-MEH was performed in seven patients with a cranially migrated lumbar disc herniation encroaching on the exiting nerve root. The disc fragments were located in the preforaminal zone in four patients, and in the preforaminal and foraminal zones in three. Results All patients experienced immediate relief from symptoms after surgery and satisfactory results at the final follow-up. Surgical complications, such as a dural tear, nerve injury, and surgical site infection, were not investigated. Conclusions TL-MEH seemed to be an effective and safe alternative minimally invasive surgical option for patients with a cranially migrated lumbar disc herniation encroaching the exiting nerve root in the preforaminal and foraminal zones. PMID:24066214

  1. Dorsal root ganglion-derived Schwann cells combined with poly(lactic-co-glycolic acid)/chitosan conduits for the repair of sciatic nerve defects in rats

    PubMed Central

    Zhao, Li; Qu, Wei; Wu, Yuxuan; Ma, Hao; Jiang, Huajun

    2014-01-01

    Schwann cells, nerve regeneration promoters in peripheral nerve tissue engineering, can be used to repair both the peripheral and central nervous systems. However, isolation and purification of Schwann cells are complicated by contamination with fibroblasts. Current reported measures are mainly limited by either high cost or complicated procedures with low cell yields or purity. In this study, we collected dorsal root ganglia from neonatal rats from which we obtained highly purified Schwann cells using serum-free melanocyte culture medium. The purity of Schwann cells (> 95%) using our method was higher than that using standard medium containing fetal bovine serum. The obtained Schwann cells were implanted into poly(lactic-co-glycolic acid)/chitosan conduits to repair 10-mm sciatic nerve defects in rats. Results showed that axonal diameter and area were significantly increased and motor functions were obviously improved in the rat sciatic nerve tissue. Experimental findings suggest that serum-free melanocyte culture medium is conducive to purify Schwann cells and poly(lactic-co-glycolic acid)/chitosan nerve conduits combined with Schwann cells contribute to restore sciatic nerve defects. PMID:25598778

  2. TREATMENT OUTCOMES OF INTRADISCAL STEROID INJECTION/SELECTIVE NERVE ROOT BLOCK FOR 161 PATIENTS WITH CERVICAL RADICULOPATHY

    PubMed Central

    ITO, KEIGO; YUKAWA, YASUTSUGU; MACHINO, MASAAKI; INOUE, TARO; OUCHIDA, JUN; TOMITA, KEISUKE; KATO, FUMIHIKO

    2015-01-01

    ABSTRACT Patients with cervical radiculopathy (CR) were treated with intradiscal injection of steroids (IDIS) and/or selective nerve root block (SNRB) at our hospital. We retrospectively report the outcomes of these nonsurgical treatments for CR. 161 patients who were followed up for >2months were enrolled in this study. Patients’ clinical manifestations were classified as arm pain, arm numbness, neck and/or scapular pain, and arm paralysis. Improvement in each manifestation was classified as "disappeared," "improved," "poor," or "worsened." Responses of "disappeared" or "improved" manifestations suggested treatment effectiveness. Final clinical outcomes were evaluated using the Odom criteria. Changes in herniated disc size were evaluated by comparing the initial and final MRI scans. On the basis of these changes, the patients were divided into regression, no-change, or progression groups. We investigated the relationship between the Odom criteria and changes observed on MRI. Effectiveness rates were 89% for arm pain, 77% for arm numbness, 82% for neck and/or scapular pain, and 76% for arm paralysis. In total, 91 patients underwent repeated MRI. In 56 patients (62%), the size of the herniated disc decreased, but 31 patients (34%) exhibited no change in disc size. The regression group showed significantly better Odom criteria results than the no-change group. In conclusion, IDIS and SNRB for CR are not widely performed. However, other extremely effective therapies that can rapidly improve neuralgia should be considered before surgery. PMID:25797986

  3. Multi-scale simulations predict responses to non-invasive nerve root stimulation

    NASA Astrophysics Data System (ADS)

    Laakso, Ilkka; Matsumoto, Hideyuki; Hirata, Akimasa; Terao, Yasuo; Hanajima, Ritsuko; Ugawa, Yoshikazu

    2014-10-01

    Objective. Established biophysical neurone models have achieved limited success in reproducing electrophysiological responses to non-invasive stimulation of the human nervous system. This is related to our insufficient knowledge of the induced electric currents inside the human body. Despite the numerous research and clinical applications of non-invasive stimulation, it is still unclear which internal sites are actually affected by it. Approach. We performed multi-scale computer simulations that, by making use of advances in computing power and numerical algorithms, combine a microscopic model of electrical excitation of neurones with a macroscopic electromagnetic model of the realistic whole-body anatomy. Main results. The simulations yield responses consistent with those experimentally recorded following magnetic and electrical motor root stimulation in human subjects, and reproduce the observed amplitudes and latencies for a wide variety of stimulation parameters. Significance. Our findings demonstrate that modern computational techniques can produce detailed predictions about which and where neurones are activated, leading to improved understanding of the physics and basic mechanisms of non-invasive stimulation and enabling potential new applications that make use of improved targeting of stimulation.

  4. Characterization of Thoracic Motor and Sensory Neurons and Spinal Nerve Roots in Canine Degenerative Myelopathy, a Potential Disease Model of Amyotrophic Lateral Sclerosis

    PubMed Central

    Morgan, Brandie R.; Coates, Joan R.; Johnson, Gayle C.; Shelton, G. Diane; Katz, Martin L.

    2014-01-01

    Canine Degenerative Myelopathy (DM) is a progressive adult-onset multisystem degenerative disease with many features in common with amyotrophic lateral sclerosis (ALS). As with some forms of ALS, DM is associated with mutations in superoxide dismutase 1 (SOD1). Clinical signs include general proprioceptive ataxia and spastic upper motor neuron paresis in pelvic limbs, which progress to flaccid tetraplegia and dysphagia. The purpose of this study was to characterize DM as a potential disease model for ALS. We previously reported that intercostal muscle atrophy develops in dogs with advanced stage DM. To determine if other components of the thoracic motor unit (MU) also demonstrated morphological changes consistent with dysfunction, histopathologic and morphometric analyses were conducted on thoracic spinal motor neurons (MN) and dorsal root ganglia (DRG), and in motor and sensory nerve root axons from DM-affected Boxers and Pembroke Welsh Corgis (PWCs). No alterations in MNs, or motor root axons were observed in either breed. However, advanced stage PWCs exhibited significant losses of sensory root axons, and numerous DRG sensory neurons displayed evidence of degeneration. These results indicate that intercostal muscle atrophy in DM is not preceded by physical loss of the motor neurons innervating these muscles, or of their axons. Axonal loss in thoracic sensory roots and sensory nerve death suggest sensory involvement may play an important role in DM disease progression. Further analysis of the mechanisms responsible for these morphological findings would aid in the development of therapeutic intervention for DM and some forms of ALS. PMID:24375814

  5. Rehabilitation Considerations of a Brachial Plexus Injury with Complete Avulsion of C5 and C6 Nerve Roots in a College Football Player

    PubMed Central

    Saliba, Susan; Saliba, Ethan N.; Pugh, Kelli F.; Chhabra, Abhinav; Diduch, David

    2009-01-01

    Severe brachial plexus injuries are rare in sports, but they have catastrophic results with a significant loss of function in the involved upper extremity. Nerve root avulsions must be timely managed with prompt evaluation, accurate diagnosis, and surgical treatment to optimize the potential for a functional outcome. This case report describes the mechanism of injury, diagnostic evolution, surgical management, and rehabilitation of a college football player who sustained a traumatic complete nerve root avulsion of C5 and C6 (upper trunk of the brachial plexus). Diagnostics included clinical evaluation, magnetic resonance imaging, computed tomography myelogram, and electromyogram. Surgical planning included nerve grafting and neurotization (nerve transfer). Rehabilitation goals were to bring the hand to the face (active biceps function), to stabilize the shoulder for abduction and flexion, and to reduce neuropathic pain. Direct current stimulation, bracing, therapeutic exercise, and biofeedback were used to maximize the use of the athlete’s upper extremity. Although the athlete could not return to sport or normal function by most standards, his results were satisfactory in that he regained an ability to perform many activities of daily living. PMID:23015895

  6. The Impact of Spinal Cord Nerve Roots and Denticulate Ligaments on Cerebrospinal Fluid Dynamics in the Cervical Spine

    PubMed Central

    Heidari Pahlavian, Soroush; Yiallourou, Theresia; Tubbs, R. Shane; Bunck, Alexander C.; Loth, Francis; Goodin, Mark; Raisee, Mehrdad; Martin, Bryn A.

    2014-01-01

    Cerebrospinal fluid (CSF) dynamics in the spinal subarachnoid space (SSS) have been thought to play an important pathophysiological role in syringomyelia, Chiari I malformation (CM), and a role in intrathecal drug delivery. Yet, the impact that fine anatomical structures, including nerve roots and denticulate ligaments (NRDL), have on SSS CSF dynamics is not clear. In the present study we assessed the impact of NRDL on CSF dynamics in the cervical SSS. The 3D geometry of the cervical SSS was reconstructed based on manual segmentation of MRI images of a healthy volunteer and a patient with CM. Idealized NRDL were designed and added to each of the geometries based on in vivo measurments in the literature and confirmation by a neuroanatomist. CFD simulations were performed for the healthy and patient case with and without NRDL included. Our results showed that the NRDL had an important impact on CSF dynamics in terms of velocity field and flow patterns. However, pressure distribution was not altered greatly although the NRDL cases required a larger pressure gradient to maintain the same flow. Also, the NRDL did not alter CSF dynamics to a great degree in the SSS from the foramen magnum to the C1 level for the healthy subject and CM patient with mild tonsillar herniation (∼6 mm). Overall, the NRDL increased fluid mixing phenomena and resulted in a more complex flow field. Comparison of the streamlines of CSF flow revealed that the presence of NRDL lead to the formation of vortical structures and remarkably increased the local mixing of the CSF throughout the SSS. PMID:24710111

  7. Edema formation in spinal nerve roots induced by experimental, graded compression. An experimental study on the pig cauda equina with special reference to differences in effects between rapid and slow onset of compression.

    PubMed

    Olmarker, K; Rydevik, B; Holm, S

    1989-06-01

    Edema formation in spinal nerve roots of the pig cauda equina was studied following experimental compression at various pressure levels, durations, and rates of onset, using a fluorescence microscopic technique. The time-pressure thresholds for the occurrence of edema in the nerve roots were: following rapid onset of compression (0.05-0.1 seconds), 2 minutes at both 50 mm Hg and 200 mm Hg, and following slow onset of compression (the pressure was slowly increased during 15-20 seconds), 2 hours at 50 mm Hg and 2 minutes at 200 mm Hg. Generally, the edema formation was more pronounced after rapid than after slow onset of compression. The data in this study also indicate that intraneural edema might be more easily formed in nerve roots than in peripheral nerves after compression injury. PMID:2546258

  8. Monitoring of immune cell response to B cell depletion therapy and nerve root injury using SPIO enhanced MRI

    NASA Astrophysics Data System (ADS)

    Thorek, Daniel L.

    2009-12-01

    Magnetic resonance (MR) is a robust platform for non-invasive, high-resolution anatomical imaging. However, MR imaging lacks the requisite sensitivity and contrast for imaging at the cellular level. This represents a clinical impediment to greater diagnostic accuracy. Recent advances have allowed for the in vivo visualization of populations and even of individual cells using superparamagnetic iron oxide (SPIO) MR contrast agents. These nanoparticles, commonly manifested as a core of a single iron oxide crystal or cluster of crystals coated in a biocompatible shell, function to shorten proton relaxation times. In MR imaging these constructs locally dephase protons, resulting in a decrease in signal (hypointensity) localized to the region of accumulation of SPIO. In the context of immune cell imaging, SPIO can provide insight into the cellular migration patterns, trafficking, temporal dynamics and progression of diseases and their related pathological states. Furthermore, by visualizing the presence and activity of immune cells, SPIO-enabled cellular imaging can help evaluate the efficacy of therapy in immune disorders. This thesis examines the production, modification and application of SPIO in a range of in vitro and in vivo immune-response-relevant cellular systems. The role of different nanoparticle characteristics including diameter, surface charge and concentration are investigated in the labeling of T cells in culture. Following optimization of SPIO loading conditions for lymphocytes, the effect these particles have on the activation of primary B cells are elucidated. B cells are tracked using a variety of modalities, with and without the application of B cell depleting therapy. This is to evaluate the efficacy of SPIO as in vivo marker for B cell distribution. Unmodified SPIO were applied to monitor macrophage infiltration in a transient nerve root compression model, with implications for neck pain diagnosis and treatment. Nanoparticle accumulation and MR

  9. Characterization of thoracic motor and sensory neurons and spinal nerve roots in canine degenerative myelopathy, a potential disease model of amyotrophic lateral sclerosis.

    PubMed

    Morgan, Brandie R; Coates, Joan R; Johnson, Gayle C; Shelton, G Diane; Katz, Martin L

    2014-04-01

    Canine degenerative myelopathy (DM) is a progressive, adult-onset, multisystem degenerative disease with many features in common with amyotrophic lateral sclerosis (ALS). As with some forms of ALS, DM is associated with mutations in superoxide dismutase 1 (SOD1). Clinical signs include general proprioceptive ataxia and spastic upper motor neuron paresis in pelvic limbs, which progress to flaccid tetraplegia and dysphagia. The purpose of this study was to characterize DM as a potential disease model for ALS. We previously reported that intercostal muscle atrophy develops in dogs with advanced-stage DM. To determine whether other components of the thoracic motor unit (MU) also demonstrated morphological changes consistent with dysfunction, histopathologic and morphometric analyses were conducted on thoracic spinal motor neurons (MNs) and dorsal root ganglia (DRG) and in motor and sensory nerve root axons from DM-affected boxers and Pembroke Welsh corgis (PWCs). No alterations in MNs or motor root axons were observed in either breed. However, advanced-stage PWCs exhibited significant losses of sensory root axons, and numerous DRG sensory neurons displayed evidence of degeneration. These results indicate that intercostal muscle atrophy in DM is not preceded by physical loss of the motor neurons innervating these muscles, nor of their axons. Axonal loss in thoracic sensory roots and sensory neuron death suggest that sensory involvement may play an important role in DM disease progression. Further analysis of the mechanisms responsible for these morphological findings would aid in the development of therapeutic intervention for DM and some forms of ALS. PMID:24375814

  10. L5 spinal nerve axotomy induces sensitization of cutaneous L4 Aβ-nociceptive dorsal root ganglion neurons in the rat in vivo.

    PubMed

    Djouhri, Laiche

    2016-06-15

    Partial nerve injury often leads to peripheral neuropathic pain (PNP), a major health problem that lacks effective drug treatment. PNP is characterized by ongoing/spontaneous pain, and hypersensitivity to noxious (hyperalgesia) and innocuous (allodynia) stimuli. Preclinical studies using the L5 spinal nerve ligation/axotomy (SNL/SNA) model of PNP suggest that this type of chronic pain results partly from sensitization of ipsilateral L4C-and Aδ-fiber nociceptive dorsal root ganglion (DRG) neurons, but whether L4 β-nociceptors, which constitute a substantial group of DRG neurons, also become sensitized remains unanswered. To address this issue, intracellular recordings from somata of cutaneous Aβ-nociceptors (classified according to their dorsal root conduction velocities (>6.5m/s), and physiologically based on their responses to noxious (but not innocuous) mechanical stimuli) were made from L4-DRGs in normal (control) rats and in rats seven days after L5 SNA in vivo. Compared with control, cutaneous L4 Aβ-nociceptive DRG neurons in SNA rats (that developed mechanical hypersensitivity) exhibited sensitization indicated by: a) decreased mean mechanical threshold (from 57.8±7.1 to 10.3±1.7mN), b) decreased mean dorsal root electrical threshold (from 11.4±0.7 to 4.3±0.4V), c) increased mean response to a suprathreshold mechanical stimulus (from 18.5±1.8 to 34±3.7spikes/sec) and d) an obvious, but non-significant, increase in the incidence of ongoing/spontaneous activity (from 3% to 18%). These findings suggest that cutaneous L4 Aβ-nociceptors also become sensitized after L5 SNA, and that sensitization of this subclass of A-fiber nociceptors may contribute both directly and indirectly to nerve injury-induced PNP. PMID:27173166

  11. Navigated Transtubular Extraforaminal Decompression of the L5 Nerve Root at the Lumbosacral Junction: Clinical Data, Radiographic Features, and Outcome Analysis.

    PubMed

    Stavrinou, P; Härtl, R; Krischek, B; Kabbasch, C; Mpotsaris, A; Goldbrunner, R

    2016-01-01

    Purpose. Extraforaminal decompression of the L5 nerve root remains a challenge due to anatomic constraints, severe level-degeneration, and variable anatomy. The purpose of this study is to introduce the use of navigation for transmuscular transtubular decompression at the L5/S1 level and report on radiological features and clinical outcome. Methods. Ten patients who underwent a navigation-assisted extraforaminal decompression of the L5 nerve root were retrospectively analyzed. Results. Six patients had an extraforaminal herniated disc and four had a foraminal stenosis. The distance between the L5 transverse process and the para-articular notch of the sacrum was 12.1 mm in patients with a herniated disc and 8.1 mm in those with a foraminal stenosis. One patient had an early recurrence and another developed dysesthesia that resolved after 3 months. There was a significant improvement from preoperative to postoperative NRS with the results being sustainable at follow-up. ODI was also significantly improved after surgery. According to the Macnab grading scale, excellent or good outcomes were obtained in 8 patients and fair ones in 2. Conclusions. The navigated transmuscular transtubular approach to the lumbosacral junction allows for optimal placement of the retractor and excellent orientation particularly for foraminal stenosis or in cases of complex anatomy. PMID:27127783

  12. Navigated Transtubular Extraforaminal Decompression of the L5 Nerve Root at the Lumbosacral Junction: Clinical Data, Radiographic Features, and Outcome Analysis

    PubMed Central

    Stavrinou, P.; Härtl, R.; Krischek, B.; Kabbasch, C.; Mpotsaris, A.; Goldbrunner, R.

    2016-01-01

    Purpose. Extraforaminal decompression of the L5 nerve root remains a challenge due to anatomic constraints, severe level-degeneration, and variable anatomy. The purpose of this study is to introduce the use of navigation for transmuscular transtubular decompression at the L5/S1 level and report on radiological features and clinical outcome. Methods. Ten patients who underwent a navigation-assisted extraforaminal decompression of the L5 nerve root were retrospectively analyzed. Results. Six patients had an extraforaminal herniated disc and four had a foraminal stenosis. The distance between the L5 transverse process and the para-articular notch of the sacrum was 12.1 mm in patients with a herniated disc and 8.1 mm in those with a foraminal stenosis. One patient had an early recurrence and another developed dysesthesia that resolved after 3 months. There was a significant improvement from preoperative to postoperative NRS with the results being sustainable at follow-up. ODI was also significantly improved after surgery. According to the Macnab grading scale, excellent or good outcomes were obtained in 8 patients and fair ones in 2. Conclusions. The navigated transmuscular transtubular approach to the lumbosacral junction allows for optimal placement of the retractor and excellent orientation particularly for foraminal stenosis or in cases of complex anatomy. PMID:27127783

  13. Differential regulation of immune responses and macrophage/neuron interactions in the dorsal root ganglion in young and adult rats following nerve injury

    PubMed Central

    2009-01-01

    Background Neuropathic pain is an apparently spontaneous experience triggered by abnormal physiology of the peripheral or central nervous system, which evolves with time. Neuropathic pain arising from peripheral nerve injury is characterized by a combination of spontaneous pain, hyperalgesia and allodynia. There is no evidence of this type of pain in human infants or rat pups; brachial plexus avulsion, which causes intense neuropathic pain in adults, is not painful when the injury is sustained at birth. Since infants are capable of nociception from before birth and display both acute and chronic inflammatory pain behaviour from an early neonatal age, it appears that the mechanisms underlying neuropathic pain are differentially regulated over a prolonged postnatal period. Results We have performed a microarray analysis of the rat L4/L5 dorsal root ganglia (DRG), 7 days post spared nerve injury, a model of neuropathic pain. Genes that are regulated in adult rats displaying neuropathic behaviour were compared to those regulated in young rats (10 days old) that did not show the same neuropathic behaviour. The results show a set of genes, differentially regulated in the adult DRG, that are principally involved in immune system modulation. A functional consequence of this different immune response to injury is that resident macrophages cluster around the large A sensory neuron bodies in the adult DRG seven days post injury, whereas the macrophages in young DRG remain scattered evenly throughout the ganglion, as in controls. Conclusions The results show, for the first time, a major difference in the neuroimmune response to nerve injury in the dorsal root ganglion of young and adult rats. Differential analysis reveals a new set of immune related genes in the ganglia, that are differentially regulated in adult neuropathic pain, and that are consistent with the selective activation of macrophages around adult, but not young large A sensory neurons post injury. These

  14. Axotomy of tributaries of the pelvic and pudendal nerves induces changes in the neurochemistry of mouse dorsal root ganglion neurons and the spinal cord.

    PubMed

    McCarthy, Carly J; Tomasella, Eugenia; Malet, Mariana; Seroogy, Kim B; Hökfelt, Tomas; Villar, Marcelo J; Gebhart, G F; Brumovsky, Pablo R

    2016-05-01

    Using immunohistochemical techniques, we characterized changes in the expression of several neurochemical markers in lumbar 4-sacral 2 (L4-S2) dorsal root ganglion (DRG) neuron profiles (NPs) and the spinal cord of BALB/c mice after axotomy of the L6 and S1 spinal nerves, major tributaries of the pelvic (targeting pelvic visceral organs) and pudendal (targeting perineum and genitalia) nerves. Sham animals were included. Expression of cyclic AMP-dependent transcription factor 3 (ATF3), calcitonin gene-related peptide (CGRP), transient receptor potential cation channel subfamily V, member 1 (TRPV1), tyrosine hydroxylase (TH) and vesicular glutamate transporters (VGLUT) types 1 and -2 was analysed seven days after injury. L6-S1 axotomy induced dramatic de novo expression of ATF3 in many L6-S1 DRG NPs, and parallel significant downregulations in the percentage of CGRP-, TRPV1-, TH- and VGLUT2-immunoreactive (IR) DRG NPs, as compared to their expression in uninjured DRGs (contralateral L6-S1-AXO; sham mice); VGLUT1 expression remained unaltered. Sham L6-S1 DRGs only showed a small ipsilateral increase in ATF3-IR NPs (other markers were unchanged). L6-S1-AXO induced de novo expression of ATF3 in several lumbosacral spinal cord motoneurons and parasympathetic preganglionic neurons; in sham mice the effect was limited to a few motoneurons. Finally, a moderate decrease in CGRP- and TRPV1-like-immunoreactivities was observed in the ipsilateral superficial dorsal horn neuropil. In conclusion, injury of a mixed visceral/non-visceral nerve leads to considerable neurochemical alterations in DRGs matched, to some extent, in the spinal cord. Changes in these and potentially other nociception-related molecules could contribute to pain due to injury of nerves in the abdominopelvic cavity. PMID:25749859

  15. Electromechanical Nerve Stimulator

    NASA Technical Reports Server (NTRS)

    Tcheng, Ping; Supplee, Frank H., Jr.; Prass, Richard L.

    1993-01-01

    Nerve stimulator applies and/or measures precisely controlled force and/or displacement to nerve so response of nerve measured. Consists of three major components connected in tandem: miniature probe with spherical tip; transducer; and actuator. Probe applies force to nerve, transducer measures force and sends feedback signal to control circuitry, and actuator positions force transducer and probe. Separate box houses control circuits and panel. Operator uses panel to select operating mode and parameters. Stimulator used in research to characterize behavior of nerve under various conditions of temperature, anesthesia, ventilation, and prior damage to nerve. Also used clinically to assess damage to nerve from disease or accident and to monitor response of nerve during surgery.

  16. Bilateral elevation of interleukin-6 protein and mRNA in both lumbar and cervical dorsal root ganglia following unilateral chronic compression injury of the sciatic nerve

    PubMed Central

    2013-01-01

    Background Current research implicates interleukin (IL)-6 as a key component of the nervous-system response to injury with various effects. Methods We used unilateral chronic constriction injury (CCI) of rat sciatic nerve as a model for neuropathic pain. Immunofluorescence, ELISA, western blotting and in situ hybridization were used to investigate bilateral changes in IL-6 protein and mRNA in both lumbar (L4-L5) and cervical (C7-C8) dorsal root ganglia (DRG) following CCI. The operated (CCI) and sham-operated (sham) rats were assessed after 1, 3, 7, and 14 days. Withdrawal thresholds for mechanical hyperalgesia and latencies for thermal hyperalgesia were measured in both ipsilateral and contralateral hind and fore paws. Results The ipsilateral hind paws of all CCI rats displayed a decreased threshold of mechanical hyperalgesia and withdrawal latency of thermal hyperalgesia, while the contralateral hind and fore paws of both sides exhibited no significant changes in mechanical or thermal sensitivity. No significant behavioral changes were found in the hind and fore paws on either side of the sham rats, except for thermal hypersensitivity, which was present bilaterally at 3 days. Unilateral CCI of the sciatic nerve induced a bilateral increase in IL-6 immunostaining in the neuronal bodies and satellite glial cells (SGC) surrounding neurons of both lumbar and cervical DRG, compared with those of naive control rats. This bilateral increase in IL-6 protein levels was confirmed by ELISA and western blotting. More intense staining for IL-6 mRNA was detected in lumbar and cervical DRG from both sides of rats following CCI. The DRG removed from sham rats displayed a similar pattern of staining for IL-6 protein and mRNA as found in naive DRG, but there was a higher staining intensity in SGC. Conclusions Bilateral elevation of IL-6 protein and mRNA is not limited to DRG homonymous to the injured nerve, but also extended to DRG that are heteronymous to the injured nerve. The

  17. Validity of the vertical tube-shift method in determining the relationship between the mandibular third molar roots and the inferior alveolar nerve canal

    PubMed Central

    2015-01-01

    Objectives To assess the validity of the vertical tube-shift method using intraoral periapical radiography (IOPAR) for determining the relationship between the mandibular third molar roots and the inferior alveolar nerve (IAN) canal in comparison with cone-beam computed tomography (CBCT). Materials and Methods Fifty impacted mandibular third molars were analyzed using the IOPAR vertical tube-shift method and CBCT. The relationship of the IAN canal to the impacted mandibular third molar was recorded as buccal, lingual or in line with the apex and was compared with CBCT findings. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the vertical tube-shift method in depicting the relationship (buccal/lingual/in line with the apex) of the IAN canal to the third molar root apex was calculated. Results The sensitivity and specificity PPV and NPV of the IOPAR vertical tube-shift technique was found to be highest for a lingual relationship (100%) followed by buccal (94.4%, 92.3%, 97.1%, and 85.7%) and in line with the apex relationship (88.9%, 95.0%, 80.0%, and 97.4%) of the IAN canal with the third molar root apex, respectively. A statistically significant association was observed between the IOPAR vertical tube-shift method and the CBCT with a P-value <0.01. Conclusion The vertical tube-shift method can be used as an effective diagnostic tool in assessing the relationship of the IAN canal to the third molar root apex with high sensitivity, specificity, PPV, and NPV. PMID:25922817

  18. Expression and transport of Angiotensin II AT1 receptors in spinal cord, dorsal root ganglia and sciatic nerve of the rat

    PubMed Central

    Pavel, Jaroslav; Tang, Hui; Brimijoin, Stephen; Moughamian, Armen; Nishioku, Tsuyoshi; Benicky, Julius; Saavedra, Juan M

    2009-01-01

    To clarify the role of Angiotensin II in the regulation of peripheral sensory and motor systems, we initiated a study of the expression, localization and transport of Angiotensin II receptor types in the rat sciatic nerve pathway, including L4–L5 spinal cord segments, the corresponding dorsal root ganglia (DRGs) and the sciatic nerve. We used quantitative autoradiography for AT1 and AT2 receptors, and in situ hybridization to detect AT1A, AT1B and AT2 mRNAs. We found substantial expression and discrete localization of Angiotensin II AT1 receptors, with much higher numbers in the grey than in the white matter. A very high AT1 receptor expression was detected in the superficial dorsal horns and in neuronal clusters of the DRGs. Expression of AT1A mRNA was significantly higher than that of AT1B. AT1 receptor binding and AT1A and AT1B mRNAs were especially prominent in ventral horn motor neurons, and in the DRG neuronal cells. Unilateral dorsal rhizotomy significantly reduced AT1 receptor binding in the ipsilateral side of the superficial dorsal horn, indicating that a substantial number of dorsal horn AT1 receptors have their origin in the DRGs. After ligation of the sciatic nerve, there was a high accumulation of AT1 receptors proximal to the ligature, a demonstration of anterograde receptor transport. We found inconsistent levels of AT2 receptor binding and mRNA. Our results suggest multiple roles of Angiotensin II AT1 receptors in the regulation of sensory and motor functions. PMID:18976642

  19. Localization of the endocannabinoid-degrading enzyme fatty acid amide hydrolase in rat dorsal root ganglion cells and its regulation after peripheral nerve injury.

    PubMed

    Lever, Isobel J; Robinson, Michelle; Cibelli, Mario; Paule, Cleoper; Santha, Peter; Yee, Louis; Hunt, Stephen P; Cravatt, Benjamin F; Elphick, Maurice R; Nagy, Istvan; Rice, Andrew S C

    2009-03-25

    Fatty acid amide hydrolase (FAAH) is a degradative enzyme for a group of endogenous signaling lipids that includes anandamide (AEA). AEA acts as an endocannabinoid and an endovanilloid by activating cannabinoid and vanilloid type 1 transient receptor potential (TRPV1) receptors, respectively, on dorsal root ganglion (DRG) sensory neurons. Inhibition of FAAH activity increases AEA concentrations in nervous tissue and reduces sensory hypersensitivity in animal pain models. Using immunohistochemistry, Western blotting, and reverse transcription-PCR, we demonstrate the location of the FAAH in adult rat DRG, sciatic nerve, and spinal cord. In naive rats, FAAH immunoreactivity localized to the soma of 32.7 +/- 0.8% of neurons in L4 and L5 DRG. These were small-sized (mean soma area, 395.96 +/- 5.6 mum(2)) and predominantly colabeled with peripherin and isolectin B4 markers of unmyelinated C-fiber neurons; 68% colabeled with antibodies to TRPV1 (marker of nociceptive DRG neurons), and <2% colabeled with NF200 (marker of large myelinated neurons). FAAH-IR was also present in small, NF200-negative cultured rat DRG neurons. Incubation of these cultures with the FAAH inhibitor URB597 increased AEA-evoked cobalt uptake in a capsazepine-sensitive manner. After sciatic nerve axotomy, there was a rightward shift in the cell-size distribution of FAAH-immunoreactive (IR) DRG neurons ipsilateral to injury: FAAH immunoreactivity was detected in larger-sized cells that colabeled with NF200. An ipsilateral versus contralateral increase in both the size and proportion of FAAH-IR DRG occurred after spinal nerve transection injury but not after chronic inflammation of the rat hindpaw 2 d after injection of complete Freund's adjuvant. This study reveals the location of FAAH in neural tissue involved in peripheral nociceptive transmission. PMID:19321773

  20. Reversal of neurochemical alterations in the spinal dorsal horn and dorsal root ganglia by Mas-related gene (Mrg) receptors in a rat model of spinal nerve injury.

    PubMed

    Wang, Dongmei; Xue, Yaping; Yan, Yanhua; Lin, Minjie; Yang, Jiajia; Huang, Jianzhong; Hong, Yanguo

    2016-07-01

    The rodent Mas-related gene (Mrg) receptor subtype C has been demonstrated to inhibit pathological pain. This study investigated the mechanisms underlying the reversal of pain hypersensitivity by the selective MrgC receptor agonist bovine adrenal medulla 8-22 (BAM8-22) in a rat model of L5 spinal nerve ligation (SNL). Intrathecal (i.t.) administration of BAM8-22 (0.1-10nmol) attenuated mechanical allodynia in a dose-dependent manner on day 10 after SNL. The antiallodynia effect of BAM8-22 was abolished by MrgC receptor antibody, but not by naloxone. I.t. BAM8-22 (10nmol) inhibited SNL-induced upregulation of neuronal nitric oxide synthesis (nNOS) and phosphorylation of cyclic AMP response element-binding protein (p-CREB) in the spinal dorsal horn. The BAM8-22 treatment reversed the SNL-induced astrocyte activation, increase of interleukin-1β (IL-1β) expression and phosphorylation of extracellular signal-regulated kinase (p-ERK) in the spinal cord. BAM8-22 also reversed the upregulation of fractalkine and IL-1β in small- and medium-sized dorsal root ganglion (DRG) neurons. Furthermore, the BAM8-22 exposure suppressed the lipopolysaccharide (LPS)-induced increase of nNOS and IL-1β in the DRG explant cultures and the BAM8-22-induced suppression disappeared in the presence of MrgC receptor antibody. The present study provides evidence that activation of MrgC receptors inhibits nerve injury-induced increase of pronociceptive molecules in DRG neurons, suppressing astrocyte activation, the upregulation of excitatory mediators and phosphorylation of transcription factors in the spinal dorsal horn. As MrgC receptors are unequally expressed in the dorsal root and trigeminal ganglia, this study suggests that targeting MrgC receptors could be a new therapy for neuropathic pain with limited unwanted effects. PMID:27018398

  1. Expression of the vesicular glutamate transporters-1 and -2 in adult mouse dorsal root ganglia and spinal cord and their regulation by nerve injury.

    PubMed

    Brumovsky, P; Watanabe, M; Hökfelt, T

    2007-06-29

    The expression of two vesicular glutamate transporters (VGLUTs), VGLUT1 and VGLUT2, was studied with immunohistochemistry in lumbar dorsal root ganglia (DRGs), the lumbar spinal cord and the skin of the adult mouse. About 12% and 65% of the total number of DRG neuron profiles (NPs) expressed VGLUT1 and VGLUT2, respectively. VGLUT1-immunoreactive (IR) NPs were usually medium- to large-sized, in contrast to a majority of small- or medium-sized VGLUT2-IR NPs. Most VGLUT1-IR NPs did not coexpress calcitonin gene-related peptide (CGRP) or bound isolectin B4 (IB4). In contrast, approximately 31% and approximately 42% of the VGLUT2-IR DRG NPs were also CGRP-IR or bound IB4, respectively. Conversely, virtually all CGRP-IR and IB4-binding NPs coexpressed VGLUT2. Moderate colocalization between VGLUT1 and VGLUT2 was also observed. Sciatic nerve transection induced a decrease in the overall number of VGLUT1- and VGLUT2-IR NPs (both ipsi- and contralaterally) and, in addition, a parallel, unilateral increase of VGLUT2-like immunoreactivity (LI) in a subpopulation of mostly small NPs. In the dorsal horn of the spinal cord, strong VGLUT1-LI was detected, particularly in deep dorsal horn layers and in the ventral horns. VGLUT2-LI was abundant throughout the gray spinal matter, 'radiating' into/from the white matter. A unilateral dorsal rhizotomy reduced VGLUT1-LI, while apparently leaving unaffected the VGLUT2-LI. Transport through axons for both VGLUTs was confirmed by their accumulation after compression of the sciatic nerve or dorsal roots. In the hind paw skin, abundant VGLUT2-IR nerve fibers were observed, sometimes associated with Merkel cells. Lower numbers of VGLUT1-IR fibers were also detected in the skin. Some VGLUT1-IR and VGLUT2-IR fibers were associated with hair follicles. Based on these data and those by Morris et al. [Morris JL, Konig P, Shimizu T, Jobling P, Gibbins IL (2005) Most peptide-containing sensory neurons lack proteins for exocytotic release and

  2. Increased expression of HCN2 channel protein in L4 dorsal root ganglion neurons following axotomy of L5- and inflammation of L4-spinal nerves in rats.

    PubMed

    Smith, T; Al Otaibi, M; Sathish, J; Djouhri, L

    2015-06-01

    A hallmark of peripheral neuropathic pain (PNP) is chronic spontaneous pain and/or hypersensitivity to normally painful stimuli (hyperalgesia) or normally nonpainful stimuli (allodynia).This pain results partly from abnormal hyperexcitability of dorsal root ganglion (DRG) neurons. We have previously shown, using a modified version of the lumbar 5 (L5)-spinal nerve ligation model of PNP (mSNA model involving L5-spinal nerve axotomy plus loose ligation of the lumbar 4 (L4)-spinal nerve with neuroinflammation-inducing chromic-gut), that L4 DRG neurons exhibit increased spontaneous activity, the key characteristic of neuronal hyperexcitability. The underlying ionic and molecular mechanisms of the hyperexcitability of L4 DRG neurons are incompletely understood, but could result from changes in expression and/or function of ion channels including hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, which are active near the neuron's resting membrane potential, and which produce an excitatory inward current that depolarizes the membrane potential toward the threshold of action potential generation. Therefore, in the present study we used the mSNA model to investigate whether: (a) expression of HCN1-HCN3 channels is altered in L4 DRG neurons which, in the mSNA model, are essential for transmission of the evoked pain, and which contribute to chronic spontaneous pain, and (b) local (intraplantar) blockade of these HCN channels, with a specific blocker, ZD7288, attenuates chronic spontaneous pain and/or evoked pain in mSNA rats. We found 7days after mSNA: (1) a significant increase in HCN2-immunoreactivity in small (<30μm) DRG neurons (predominantly IB4-negative neurons), and in the proportion of small neurons expressing HCN2 (putative nociceptors); (2) no significant change in HCN1- or HCN3-immunoreactivity in all cell types; and (3) attenuation, with ZD7288 (100μM intraplantar), of chronic spontaneous pain behavior (spontaneous foot lifting) and mechanical

  3. Genetic variability in the rat Aplec C-type lectin gene cluster regulates lymphocyte trafficking and motor neuron survival after traumatic nerve root injury

    PubMed Central

    2013-01-01

    Background C-type lectin (CLEC) receptors are important for initiating and shaping immune responses; however, their role in inflammatory reactions in the central nervous system after traumatic injuries is not known. The antigen-presenting lectin-like receptor gene complex (Aplec) contains a few CLEC genes, which differ genetically among inbred rat strains. It was originally thought to be a region that regulates susceptibility to autoimmune arthritis, autoimmune neuroinflammation and infection. Methods The inbred rat strains DA and PVG differ substantially in degree of spinal cord motor neuron death following ventral root avulsion (VRA), which is a reproducible model of localized nerve root injury. A large F2 (DAxPVG) intercross was bred and genotyped after which global expressional profiling was performed on spinal cords from F2 rats subjected to VRA. A congenic strain, Aplec, created by transferring a small PVG segment containing only seven genes, all C-type lectins, ontoDA background, was used for further experiments together with the parental strains. Results Global expressional profiling of F2 (DAxPVG) spinal cords after VRA and genome-wide eQTL mapping identified a strong cis-regulated difference in the expression of Clec4a3 (Dcir3), a C-type lectin gene that is a part of the Aplec cluster. Second, we demonstrate significantly improved motor neuron survival and also increased T-cell infiltration into the spinal cord of congenic rats carrying Aplec from PVG on DA background compared to the parental DA strain. In vitro studies demonstrate that the Aplec genes are expressed on microglia and upregulated upon inflammatory stimuli. However, there were no differences in expression of general microglial activation markers between Aplec and parental DA rats, suggesting that the Aplec genes are involved in the signaling events rather than the primary activation of microglia occurring upon nerve root injury. Conclusions In summary, we demonstrate that a genetic variation

  4. A diagnosis challenge-L4 nerve root compression as the initial presentation of chronic inflammatory demyelinating polyneuropathy.

    PubMed

    Cojocaru, Inimioara Mihaela; Alexianu, Marilena; Bastian, Alexandra; Sapira, Violeta; Herţea, Cristina; Cojocaru, M

    2012-01-01

    The authors present the case of a 65-year-old woman who was admitted for paraparesis and paresthesias in the inferior limbs. The neurological examination revealed the difficulty in extension of the right foot and of the right toe, accompanied by paresthesias located in the anterolateral area of the right leg, dorsum and plantar area of the foot, the reduction of the right knee jerk, and of the ankle tendon jerk both sides. The vertebro-spinal MRI showed lumbar canal stenosis with L4 intraforaminal compression on the right, and L2-L3 on the left. CSF examination revealed mild increase in protein concentration. The morphological picture of the sural nerve biopsy was compatible with a chronic inflammatory neuropathy and severe muscular lesions of neurogenic origin were observed on right gastrocnemius muscle biopsy. The diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP) was established. Solu-medrol (0.5 g/d)-5 days, then medrol (prednisolone) was done, followed by improving of the symptomatology. For the relapse of the disease intravenous immunoglobulins (IVIG)-0.4 g/kg/d-5 days was the elective treatment. Six months later she presented a new relapse. IVIG were administered with the remission of the sensitive symptoms. A chronic treatment with medrol was recommended. The diagnosis of L4 disc herniation was obvious in the studied case, but the electroneurographic examination brought extra data for the associated diagnosis of CIDP whose onset was asymmetrical and initially paucisymptomatic. Neither the electroneurographic examination nor the CSF examination were total relevant for CIDP, imposing the sural nerve biopsy. The diagnosis of CIDP involves a team-work composed of neurologist, electroneurophysiologist and neuropathologist. PMID:23610977

  5. Impacts of anti-nerve growth factor antibody on pain-related behaviors and expressions of opioid receptor in spinal dorsal horn and dorsal root ganglia of rats with cancer-induced bone pain

    PubMed Central

    Ding, Yuanyuan; Wang, Zhibin; Ma, Jiaming; Hong, Tao; Zhu, Yongqiang; Li, Hongxi; Pan, Shinong

    2016-01-01

    Objective To investigate the impacts of anti-nerve growth factor antibody on pain-related behaviors and expressions of μ-opioid receptor in spinal dorsal horn and dorsal root ganglia of rats with cancer-induced bone pain. Methods The rats were randomly grouped and then injected with 10 μl of phosphate buffer saline or Walker256 tumor cells into the upper segment of left tibia. Thirteen days after the injection, the intrathecal catheterization was performed, followed by the injection of saline, anti-nerve growth factor, nerve growth factor, and naloxone twice a day. The pain ethological changes were measured at the set time points; the expression changes of μ-opioid receptor protein and mRNA in spinal dorsal horn and dorsal root ganglia were detected on the 18th day. Results After the tumor cells were injected into the tibia, hyperalgesia appeared and the expression of μ-opioid receptor protein and mRNA in spinal dorsal horn and dorsal root ganglia was increased, compared with the sham group; after intrathecally injected anti-nerve growth factor, the significant antinociceptive effects appeared, and the μ-opioid receptor expression was increased, compared with the cancer pain group; the μ-opioid receptor expressions in the other groups showed no statistical significance. The naloxone pretreatment could mostly inverse the antinociception effects of anti-nerve growth factor. Conclusions Anti-nerve growth factor could reduce hyperalgesia in the cancer-induced bone pain rats, and the antinociceptive effects were related with the upregulation of μ-opioid receptor. PMID:27118770

  6. Effects of sciatic nerve transection on glucose uptake in the presence and absence of lactate in the frog dorsal root ganglia and spinal cord.

    PubMed

    Rigon, F; Horst, A; Kucharski, L C; Silva, R S M; Faccioni-Heuser, M C; Partata, W A

    2014-08-01

    Frogs have been used as an alternative model to study pain mechanisms because the simplicity of their nervous tissue and the phylogenetic aspect of this question. One of these models is the sciatic nerve transection (SNT), which mimics the clinical symptoms of "phantom limb", a condition that arises in humans after amputation or transverse spinal lesions. In mammals, the SNT increases glucose metabolism in the central nervous system, and the lactate generated appears to serve as an energy source for nerve cells. An answerable question is whether there is elevated glucose uptake in the dorsal root ganglia (DRG) after peripheral axotomy. As glucose is the major energy substrate for frog nervous tissue, and these animals accumulate lactic acid under some conditions, bullfrogs Lithobates catesbeianus were used to demonstrate the effect of SNT on DRG and spinal cord 1-[14C] 2-deoxy-D-glucose (14C-2-DG) uptake in the presence and absence of lactate. We also investigated the effect of this condition on the formation of 14CO2 from 14C-glucose and 14C-L-lactate, and plasmatic glucose and lactate levels. The 3-O-[14C] methyl-D-glucose (14C-3-OMG) uptake was used to demonstrate the steady-state tissue/medium glucose distribution ratio under these conditions. Three days after SNT, 14C-2-DG uptake increased, but 14C-3-OMG uptake remained steady. The increase in 14C-2-DG uptake was lower when lactate was added to the incubation medium. No change was found in glucose and lactate oxidation after SNT, but lactate and glucose levels in the blood were reduced. Thus, our results showed that SNT increased the glucose metabolism in the frog DRG and spinal cord. The effect of lactate on this uptake suggests that glucose is used in glycolytic pathways after SNT. PMID:25627385

  7. Upregulation of Chemokine CXCL12 in the Dorsal Root Ganglia and Spinal Cord Contributes to the Development and Maintenance of Neuropathic Pain Following Spared Nerve Injury in Rats.

    PubMed

    Bai, Liying; Wang, Xinru; Li, Zhisong; Kong, Cunlong; Zhao, Yonghui; Qian, Jun-Liang; Kan, Quancheng; Zhang, Wei; Xu, Ji-Tian

    2016-02-01

    Emerging evidence indicates that CXCL12/CXCR4 signaling is involved in chronic pain. However, few studies have systemically assessed its role in direct nerve injury-induced neuropathic pain and the underlying mechanism. Here, we determined that spared nerve injury (SNI) increased the expression of CXCL12 and its cognate receptor CXCR4 in lumbar 5 dorsal root ganglia (DRG) neurons and satellite glial cells. SNI also induced long-lasting upregulation of CXCL12 and CXCR4 in the ipsilateral L4-5 spinal cord dorsal horn, characterized by CXCL12 expression in neurons and microglia, and CXCR4 expression in neurons and astrocytes. Moreover, SNI-induced a sustained increase in TNF-α expression in the DRG and spinal cord. Intraperitoneal injection (i.p.) of the TNF-α synthesis inhibitor thalidomide reduced the SNI-induced mechanical hypersensitivity and inhibited the expression of CXCL12 in the DRG and spinal cord. Intrathecal injection (i.t.) of the CXCR4 antagonist AMD3100, both 30 min before and 7 days after SNI, reduced the behavioral signs of allodynia. Rats given an i.t. or i.p. bolus of AMD3100 on day 8 of SNI exhibited attenuated abnormal pain behaviors. The neuropathic pain established following SNI was also impaired by i.t. administration of a CXCL12-neutralizing antibody. Moreover, repetitive i.t. AMD3100 administration prevented the activation of ERK in the spinal cord. The mechanical hypersensitivity induced in naïve rats by i.t. CXCL12 was alleviated by pretreatment with the MEK inhibitor PD98059. Collectively, our results revealed that TNF-α might mediate the upregulation of CXCL12 in the DRG and spinal cord following SNI, and that CXCL12/CXCR4 signaling via ERK activation contributes to the development and maintenance of neuropathic pain. PMID:26781879

  8. Extracellular Nm23H1 stimulates neurite outgrowth from dorsal root ganglia neurons in vitro independently of nerve growth factor supplementation or its nucleoside diphosphate kinase activity

    SciTech Connect

    Wright, K.T.; Seabright, R.; Logan, A.; Lilly, A.J.; Khanim, F.; Bunce, C.M.; Johnson, W.E.B.

    2010-07-16

    Research highlights: {yields} Extracellular Nm23H1 stimulates nerve growth. {yields} Extracellular Nm23H1 provides pathfinding cues to growth cones. {yields} The neurotrophic activity of Nm23H1 is independent of NDP kinase activity. {yields} The neurotrophic activity of Nm23H1 is independent of NGF. -- Abstract: The nucleoside diphosphate (NDP) kinase, Nm23H1, is a highly expressed during neuronal development, whilst induced over-expression in neuronal cells results in increased neurite outgrowth. Extracellular Nm23H1 affects the survival, proliferation and differentiation of non-neuronal cells. Therefore, this study has examined whether extracellular Nm23H1 regulates nerve growth. We have immobilised recombinant Nm23H1 proteins to defined locations of culture plates, which were then seeded with explants of embryonic chick dorsal root ganglia (DRG) or dissociated adult rat DRG neurons. The substratum-bound extracellular Nm23H1 was stimulatory for neurite outgrowth from chick DRG explants in a concentration-dependent manner. On high concentrations of Nm23H1, chick DRG neurite outgrowth was extensive and effectively limited to the location of the Nm23H1, i.e. neuronal growth cones turned away from adjacent collagen-coated substrata. Nm23H1-coated substrata also significantly enhanced rat DRG neuronal cell adhesion and neurite outgrowth in comparison to collagen-coated substrata. These effects were independent of NGF supplementation. Recombinant Nm23H1 (H118F), which does not possess NDP kinase activity, exhibited the same activity as the wild-type protein. Hence, a novel neuro-stimulatory activity for extracellular Nm23H1 has been identified in vitro, which may function in developing neuronal systems.

  9. Caspase-2 Is Upregulated after Sciatic Nerve Transection and Its Inhibition Protects Dorsal Root Ganglion Neurons from Apoptosis after Serum Withdrawal

    PubMed Central

    Vigneswara, Vasanthy; Berry, Martin

    2013-01-01

    Sciatic nerve (SN) transection-induced apoptosis of dorsal root ganglion neurons (DRGN) is one factor determining the efficacy of peripheral axonal regeneration and the return of sensation. Here, we tested the hypothesis that caspase-2 (CASP2) orchestrates apoptosis of axotomised DRGN both in vivo and in vitro by disrupting the local neurotrophic supply to DRGN. We observed significantly elevated levels of cleaved CASP2 (C-CASP2), compared to cleaved caspase-3 (C-CASP3), within TUNEL+DRGN and DRG glia (satellite and Schwann cells) after SN transection. A serum withdrawal cell culture model, which induced 40% apoptotic death in DRGN and 60% in glia, was used to model DRGN loss after neurotrophic factor withdrawal. Elevated C-CASP2 and TUNEL were observed in both DRGN and DRG glia, with C-CASP2 localisation shifting from the cytosol to the nucleus, a required step for induction of direct CASP2-mediated apoptosis. Furthermore, siRNA-mediated downregulation of CASP2 protected 50% of DRGN from apoptosis after serum withdrawal, while downregulation of CASP3 had no effect on DRGN or DRG glia survival. We conclude that CASP2 orchestrates the death of SN-axotomised DRGN directly and also indirectly through loss of DRG glia and their local neurotrophic factor support. Accordingly, inhibiting CASP2 expression is a potential therapy for improving both the SN regeneration response and peripheral sensory recovery. PMID:23451279

  10. Deficits in foot skin sensation are related to alterations in balance control in chronic low back patients experiencing clinical signs of lumbar nerve root impingement.

    PubMed

    Frost, Lydia R; Bijman, Marc; Strzalkowski, Nicholas D J; Bent, Leah R; Brown, Stephen H M

    2015-05-01

    Chronic low back pain (LBP) patients with radiculopathy, or sciatica, experience pain, tingling or numbness radiating down their leg due to compression of the lumbar nerve root. The resulting reduction in somatosensory information from the foot sole may contribute to deficits in standing balance control. This work was designed to investigate the relationship between foot skin sensitivity and standing balance control in chronic LBP patients with associated radiculopathy. Patients (n=9) and matched healthy controls (n=9) were recruited to the study, and were tested for balance control in both quiet standing as well as during rapid arm raise perturbation trials on a force plate. Foot skin sensitivity was tested bilaterally for vibratory threshold (3, 40 and 250 Hz) and touch (monofilament) threshold. Results demonstrate that patients had reduced sensitivity to 250 Hz vibration in their affected compared to unaffected foot (at the great toe and heel), as well as compared to controls (at the great toe), but there were no differences with lower frequency vibratory testing or with monofilament testing. While there were no significant between-group differences in balance measures, moderate statistically significant correlations between 250 Hz sensitivity and quiet standing balance parameters were uncovered. Thus, patients demonstrate reduced high-frequency vibratory sensitivity at the foot sole, and correlations with quiet standing balance measures indicate a connection between these foot skin sensitivity deficits and alterations in balance control. Clinically, this identifies high frequency vibration testing as an important measure of skin sensitivity in patients with radiculopathy. PMID:25887249

  11. Normative Values for Intertrial Variability of Motor Responses to Nerve Root and Transcranial Stimulation: A Condition for Follow-Up Studies in Individual Subjects

    PubMed Central

    Malucchi, Simona; Capobianco, Marco; Sperli, Francesca

    2016-01-01

    Objective Intertrial variability (ITV) of motor responses to peripheral (CMAP) and transcranial (MEP) stimulation prevents their use in follow-up studies. Our purpose was to develop strategies to reduce and measure CMAP and MEP ITV to guide long-term monitoring of conduction slowing and conduction failure of peripheral and central motor pathway in the individual patient. Methods Maximal compound muscle action potentials to High Voltage Electrical Stimulation (HVES) of lumbo-sacral nerve roots (r-CMAP) and activated, averaged motor evoked potentials (MEPs) to Transcranial Magnetic Stimulation (TMS) using double cone coil were recorded from 10 proximal and distal muscle districts of lower limbs. The procedure was repeated twice, 1–2 days apart, in 30 subjects, including healthy volunteers and clinically stable multiple sclerosis patients, using constant stimulating and recording sites and adopting a standardized procedure of voluntary activation. ITV for latency and area indexes and for the ratio between MEP and r-CMAP areas (a-Ratio) was expressed as Relative Intertrial Variation (RIV, 5th-95th percentile). As an inverse correlation between the size of area and ITV was found, raw ITV values were normalized as a function of area to make them comparable with one another. Results All RIV values for latencies were significantly below the optimum threshold of ± 10%, with the exception of r-CMAP latencies recorded from Vastus Lateralis muscle. RIVs for a-Ratio, the most important index of central conduction failure, ranged from a maximum of -25.3% to +32.2% (Vastus Medialis) to a minimum of -15.0% to + 17.4% (Flexor Hallucis Brevis). Conclusions The described procedure represents an effort to lower as much as possible variability of motor responses in serial recording; the reported ITV normative values are the necessary premise to detect significant changes of motor conduction slowing and failure in the individual patient in follow-up studies. PMID:27182973

  12. Expression patterns of T-type Cav3.2 channel and insulin-like growth factor-1 receptor in dorsal root ganglion neurons of mice after sciatic nerve axotomy.

    PubMed

    Lin, Si-Fang; Yu, Xiao-Lu; Liu, Xiao-Ya; Wang, Bing; Li, Cheng-Hui; Sun, Yan-Gang; Liu, Xing-Jun

    2016-10-19

    Substantial evidence indicates that T-type Cav3.2 channel and insulin-like growth factor-1 (IGF-1) contribute to pain hypersensitivity within primary sensory nerves. A recent study suggested that activation of IGF-1 receptor (IGF-1R) could increase Cav3.2 channel currents and further contribute to inflammatory pain sensitivity. However, the expression patterns of Cav3.2 and IGF-1R and their colocalization in dorsal root ganglion (DRG) in chronic neuropathic pain condition remain unknown. In this study, we explored expression patterns of Cav3.2, IGF-1R and their colocalization, and whether phenotypic switch occurs in a subpopulation of Cav3.2 or IGF-1R neurons in mouse DRGs after sciatic nerve axotomy with immunofluorescence, real-time reverse transcription-PCR, and western blot assays. We found that expressions of Cav3.2 and IGF-1R, and their colocalization were not increased in DRGs of mice following axotomy. In addition, Cav3.2 or IGF-1R subpopulation neurons did not acquire significant switch in expression phenotype after sciatic nerve axotomy. Our findings argue for an upregulation of Cav3.2 and IGF-1R expression in lumbar DRGs post-sciatic nerve axotomy and provided an insight for understanding the functions of peripheral afferent Cav3.2 channel and IGF-1/IGF-1R signaling in chronic neuropathic pain. PMID:27571431

  13. Nerve biopsy

    MedlinePlus

    Nerve biopsy may be done to help diagnose: Axon degeneration (destruction of the axon portion of the nerve cell) Damage to the ... Demyelination Inflammation of the nerve Leprosy Loss of axon tissue Metabolic neuropathies Necrotizing vasculitis Sarcoidosis

  14. Pinched Nerve

    MedlinePlus

    ... Enhancing Diversity Find People About NINDS NINDS Pinched Nerve Information Page Table of Contents (click to jump ... being done? Clinical Trials Organizations What is Pinched Nerve? The term "pinched nerve" is a colloquial term ...

  15. steve bAccumulation of nerve growth factor and its receptors in the uterus and dorsal root ganglia in a mouse model of adenomyosis

    PubMed Central

    2011-01-01

    Background Adenomyosis is a common gynecological disease, which is accompanied by a series of immunological and neuroendocrinological changes. Nerve growth factor (NGF) plays a critical role in producing pain, neural plasticity, immunocyte aggregation and release of inflammatory factors. This study aimed to investigate the expression of NGF and its two receptors in uteri and dorsal root ganglia (DRG) in an adenomyosis mouse model, as well as their relationship with the severity of adenomyosis. Methods Forty newborn ICR mice were randomly divided into the adenomyosis model group and control group (n = 20 in each group). Mice in the adenomyosis model group were orally dosed with 2.7 μmol/kg tamoxifen on days 2-5 after birth. Experiments were conducted to identify the expression of NGF- beta and its receptors, tyrosine kinase receptor (trkA) and p75 neurotrophin receptor (p75NTR), in the uterus and DRG in four age groups (90+/-5 d, 140+/-5 d, 190+/-5 d and 240+/-5 d; n = 5 mice in each group) by western bolt, immunochemistry and real time reverse transcription-polymerase chain reaction. Results Adenomyosis, which became more serious as age increased, was successfully induced in dosed ICR mice. NGF-beta, trkA and p75NTR protein levels in the uterus and trkA mRNA levels in DRG were higher in the older aged adenomyosis model group than those in controls (190+/-5 d and 240+/-5 d groups, P < 0.05). The expression of NGF-beta and its receptors in the uterus increased gradually as age increased for adenomyosis mice (190+/-5 d and 240+/-5 d, P < 0.05, compared with 90+/-5 d) but it showed little change in control mice. The mRNA level of trkA in DRG also increased as age increased in the adenomyosis model group (190+/-5 d and 240+/-5 d, P < 0.05, compared with 90+/-5 d) but was unchanged in controls. The mRNA level of p75NTR in DRG was not different between the adenomyosis and control groups and was stable from young to old mice. Conclusions NGF- beta can be used as an

  16. Non-invasive electrical and magnetic stimulation of the brain, spinal cord, roots and peripheral nerves: Basic principles and procedures for routine clinical and research application. An updated report from an I.F.C.N. Committee.

    PubMed

    Rossini, P M; Burke, D; Chen, R; Cohen, L G; Daskalakis, Z; Di Iorio, R; Di Lazzaro, V; Ferreri, F; Fitzgerald, P B; George, M S; Hallett, M; Lefaucheur, J P; Langguth, B; Matsumoto, H; Miniussi, C; Nitsche, M A; Pascual-Leone, A; Paulus, W; Rossi, S; Rothwell, J C; Siebner, H R; Ugawa, Y; Walsh, V; Ziemann, U

    2015-06-01

    These guidelines provide an up-date of previous IFCN report on "Non-invasive electrical and magnetic stimulation of the brain, spinal cord and roots: basic principles and procedures for routine clinical application" (Rossini et al., 1994). A new Committee, composed of international experts, some of whom were in the panel of the 1994 "Report", was selected to produce a current state-of-the-art review of non-invasive stimulation both for clinical application and research in neuroscience. Since 1994, the international scientific community has seen a rapid increase in non-invasive brain stimulation in studying cognition, brain-behavior relationship and pathophysiology of various neurologic and psychiatric disorders. New paradigms of stimulation and new techniques have been developed. Furthermore, a large number of studies and clinical trials have demonstrated potential therapeutic applications of non-invasive brain stimulation, especially for TMS. Recent guidelines can be found in the literature covering specific aspects of non-invasive brain stimulation, such as safety (Rossi et al., 2009), methodology (Groppa et al., 2012) and therapeutic applications (Lefaucheur et al., 2014). This up-dated review covers theoretical, physiological and practical aspects of non-invasive stimulation of brain, spinal cord, nerve roots and peripheral nerves in the light of more updated knowledge, and include some recent extensions and developments. PMID:25797650

  17. Nerve biopsy

    MedlinePlus

    ... Loss of axon tissue Metabolic neuropathies Necrotizing vasculitis Sarcoidosis Risks Allergic reaction to the local anesthetic Discomfort ... Neurosarcoidosis Peripheral neuropathy Primary amyloidosis Radial nerve dysfunction Sarcoidosis Tibial nerve dysfunction Update Date 6/1/2015 ...

  18. Nerve conduction

    MedlinePlus Videos and Cool Tools

    ... the spinal cord to muscles and sensory receptors. A peripheral nerve is composed of nerve bundles (fascicles) ... two neurons, it must first be converted to a chemical signal, which then crosses a space of ...

  19. Cranial Nerves IX, X, XI, and XII

    PubMed Central

    Sanders, Richard D.

    2010-01-01

    This article concludes the series on cranial nerves, with review of the final four (IX–XII). To summarize briefly, the most important and common syndrome caused by a disorder of the glossopharyngeal nerve (craniel nerve IX) is glossopharyngeal neuralgia. Also, swallowing function occasionally is compromised in a rare but disabling form of tardive dyskinesia called tardive dystonia, because the upper motor portion of the glossopharyngel nerve projects to the basal ganglia and can be affected by lesions in the basal ganglia. Vagus nerve funtion (craniel nerve X) can be compromised in schizophrenia, bulimia, obesity, and major depression. A cervical lesion to the nerve roots of the spinal accessory nerve (craniel nerve XI) can cause a cervical dystonia, which sometimes is misdiagnosed as a dyskinesia related to neuroleptic use. Finally, unilateral hypoglossal (craniel nerve XII) nerve palsy is one of the most common mononeuropathies caused by brain metastases. Supranuclear lesions of cranial nerve XII are involved in pseudobulbar palsy and ALS, and lower motor neuron lesions of cranial nerve XII can also be present in bulbar palsy and in ALS patients who also have lower motor neuron involvement. This article reviews these and other syndromes related to cranial nerves IX through XII that might be seen by psychiatry. PMID:20532157

  20. Reinnervation of Urethral and Anal Sphincters With Femoral Motor Nerve to Pudendal Nerve Transfer

    PubMed Central

    Ruggieri, Michael R.; Braverman, Alan S.; Bernal, Raymond M.; Lamarre, Neil S.; Brown, Justin M.; Barbe, Mary F.

    2012-01-01

    Aims Lower motor neuron damage to sacral roots or nerves can result in incontinence and a flaccid urinary bladder. We showed bladder reinnervation after transfer of coccygeal to sacral ventral roots, and genitofemoral nerves (L1, 2 origin) to pelvic nerves. This study assesses the feasibility of urethral and anal sphincter reinnervation using transfer of motor branches of the femoral nerve (L2–4 origin) to pudendal nerves (S1, 2 origin) that innervate the urethral and anal sphincters in a canine model. Methods Sacral ventral roots were selected by their ability to stimulate bladder, urethral sphincter, and anal sphincter contraction and transected. Bilaterally, branches of the femoral nerve, specifically, nervus saphenous pars muscularis [Evans HE. Miller’s anatomy of the dog. Philadelphia: W.B. Saunders; 1993], were transferred and end-to-end anastomosed to transected pudendal nerve branches in the perineum, then enclosed in unipolar nerve cuff electrodes with leads to implanted RF micro-stimulators. Results Nerve stimulation induced increased anal and urethral sphincter pressures in five of six transferred nerves. Retrograde neurotracing from the bladder, urethral sphincter, and anal sphincter using fluorogold, fast blue, and fluororuby, demonstrated urethral and anal sphincter labeled neurons in L2–4 cord segments (but not S1–3) in nerve transfer canines, consistent with rein-nervation by the transferred femoral nerve motor branches. Controls had labeled neurons only in S1–3 segments. Postmortem DiI and DiO labeling confirmed axonal regrowth across the nerve repair site. Conclusions These results show spinal cord reinnervation of urethral and anal sphincter targets after sacral ventral root transection and femoral nerve transfer (NT) to the denervated pudendal nerve. These surgical procedures may allow patients to regain continence. PMID:21953679

  1. Lateral displacement and rotational displacement sensor

    DOEpatents

    Duden, Thomas

    2014-04-22

    A position measuring sensor formed from opposing sets of capacitor plates measures both rotational displacement and lateral displacement from the changes in capacitances as overlapping areas of capacitors change. Capacitances are measured by a measuring circuit. The measured capacitances are provided to a calculating circuit that performs calculations to obtain angular and lateral displacement from the capacitances measured by the measuring circuit.

  2. A New Rerouting Technique for the Extensor Pollicis Longus in Palliative Treatment for Wrist and Finger Extension Paralysis Resulting From Radial Nerve and C5C6C7 Root Injury.

    PubMed

    Laravine, Jennifer; Cambon-Binder, Adeline; Belkheyar, Zoubir

    2016-03-01

    Wrist and finger extension paralysis is a consequence of an injury to the radial nerve or the C5C6C7 roots. Despite these 2 different levels of lesions, palliative treatment for this type of paralysis depends on the same tendon transfers. A large majority of the patients are able to compensate for a deficiency of the extension of the wrist and fingers. However, a deficiency in the opening of the first web space, which could be responsible for transfers to the abductor pollicis longus, the extensor pollicis brevis, and the extensor pollicis longus (EPL), frequently exists. The aim of this work was to evaluate the feasibility of a new EPL rerouting technique outside of Lister's tubercle. Another aim was to verify whether this technique allows a better opening of the thumb-index pinch in this type of paralysis. In the first part, we performed an anatomic study comparing the EPL rerouting technique and the frequently used technique for wrist and finger extension paralyses. In the second part, we present 2 clinical cases in which this new technique will be practiced. Preliminary results during this study favor the EPL rerouting technique. This is a simple and reproducible technique that allows for good opening of the first web space in the treatment of wrist and finger extension paralysis. PMID:26709570

  3. Clarifying the nomenclature of intervertebral disc degeneration and displacement: from bench to bedside

    PubMed Central

    Wang, Hai-Qiang; Samartzis, Dino

    2014-01-01

    As a significant determinant of low back pain, intervertebral disc degeneration (IDD) has attracted more and more attention of both investigators and physicians. Disc herniation, termed as intervertebral disc displacement, is amongst the most prevalent spinal diseases closely linked with IDD. Due to the same origins and similar pathophysiology, the ambiguity regarding the similarity and difference of IDD and intervertebral disc displacement thus remains. The aim of this study was to clarify the nomenclature of IDD and disc herniation in terms of molecular etiology, pathophysiology, nature history and clinical outcomes. Collectively, IDD is a type of multifaceted, progressive spinal disease with or without clinical symptoms as back pain, characterized by extracellular matrix and the integrity of NP and AF lost, fissures formation. Disc herniation (termed as intervertebral disc displacement) is a type of spinal disease based on IDD or not, with local pain and/or sciatica due to mechanical compression and autoimmune cascades upon the corresponding nerve roots. Clarifying the nomenclature of intervertebral disc degeneration and displacement has important implications both for investigators and for physicians. PMID:24817926

  4. Neurophysiological approach to disorders of peripheral nerve.

    PubMed

    Crone, Clarissa; Krarup, Christian

    2013-01-01

    Disorders of the peripheral nerve system (PNS) are heterogeneous and may involve motor fibers, sensory fibers, small myelinated and unmyelinated fibers and autonomic nerve fibers, with variable anatomical distribution (single nerves, several different nerves, symmetrical affection of all nerves, plexus, or root lesions). Furthermore pathological processes may result in either demyelination, axonal degeneration or both. In order to reach an exact diagnosis of any neuropathy electrophysiological studies are crucial to obtain information about these variables. Conventional electrophysiological methods including nerve conduction studies and electromyography used in the study of patients suspected of having a neuropathy and the significance of the findings are discussed in detail and more novel and experimental methods are mentioned. Diagnostic considerations are based on a flow chart classifying neuropathies into eight categories based on mode of onset, distribution, and electrophysiological findings, and the electrophysiological characteristics in each type of neuropathy are discussed. PMID:23931776

  5. Selective regulation of 3 alpha-hydroxysteroid oxido-reductase expression in dorsal root ganglion neurons: a possible mechanism to cope with peripheral nerve injury-induced chronic pain.

    PubMed

    Patte-Mensah, Christine; Meyer, Laurence; Schaeffer, Véronique; Mensah-Nyagan, Ayikoe G

    2010-09-01

    The enzyme 3alpha-hydroxysteroid oxido-reductase (3alpha-HSOR) catalyzes the synthesis and bioavailability of 3alpha,5alpha-neurosteroids as allopregnanolone (3alpha,5alpha-THP) which activates GABA(A) receptors and blocks T-type calcium channels involved in pain mechanisms. Here, we used a multidisciplinary approach to demonstrate that 3alpha-HSOR is a cellular target the modulation of which in dorsal root ganglia (DRG) may contribute to suppress pain resulting from peripheral nerve injury. Immunohistochemistry and confocal microscope analyses showed 3alpha-HSOR-immunostaining in naive rat DRG sensory neurons and glial cells. Pulse-chase, high performance liquid chromatography and Flo/One characterization of neurosteroids demonstrated 3alpha,5alpha-THP production in DRG. Behavioral methods allowed identification of pain symptoms (thermal and mechanical hyperalgesia and/or allodynia) in rats subjected to sciatic nerve chronic constriction injury (CCI). Reverse transcription and real-time polymerase chain reaction revealed that 3alpha-HSOR mRNA concentration in CCI-rat ipsilateral DRG, 5-fold higher than in contralateral DRG, was also 4- to 6-fold elevated than that in sham-operated or naive rat DRG. Consistently, Western blotting confirmed increased 3alpha-HSOR protein levels in CCI-rat ipsilateral DRG and double immunolabeling showed that 3alpha-HSOR overexpression occurred in DRG neurons but not in glia. Functional plasticity of 3alpha-HSOR leading to increased 3alpha,5alpha-THP production was evidenced in CCI-rat DRG. Interestingly, behavioral and molecular time-course investigations revealed that 3alpha-HSOR gene upregulation was correlated to pain symptom development. Most importantly, in vivo knockdown of 3alpha-HSOR expression in healthy rat DRG using 6-carboxyfluorescein-3alpha-HSOR-siRNA exacerbated thermal and mechanical pain perceptions. This paper is the first to show that siRNA-induced knockdown of a key neurosteroid-synthesizing enzyme directly

  6. Optic nerve atrophy

    MedlinePlus

    Optic nerve atrophy is damage to the optic nerve. The optic nerve carries images of what the eye sees to ... problem most often affects older adults. The optic nerve can also be damaged by shock, toxins, radiation, ...

  7. Peripheral Nerve Disorders

    MedlinePlus

    ... spinal cord. Like static on a telephone line, peripheral nerve disorders distort or interrupt the messages between the brain ... body. There are more than 100 kinds of peripheral nerve disorders. They can affect one nerve or many nerves. ...

  8. Nerve biopsy (image)

    MedlinePlus

    Nerve biopsy is the removal of a small piece of nerve for examination. Through a small incision, a sample ... is removed and examined under a microscope. Nerve biopsy may be performed to identify nerve degeneration, identify ...

  9. A precision mechanical nerve stimulator

    NASA Technical Reports Server (NTRS)

    Tcheng, Ping; Supplee, Frank H., Jr.; Prass, Richard L.

    1988-01-01

    An electromechanical device, used to apply and monitor stimulating pulses to a mammalian motor nerve, has been successfully developed at NASA Langley Research Center. Two existing force transducers, a flight skin friction balance and a miniature skin friction balance which were designed for making aerodynamic drag measurements, were modified and incorporated to form this precision instrument. The nerve stimulator is a type one servomechanism capable of applying and monitoring stimulating pulses of 0 to 10 grams with a precision of better than +/- 0.05 grams. Additionally, the device can be independently used to apply stimulating pulses by displacing the nerve from 0 to 0.25 mm with a precision of better than +/- 0.001 mm while measuring the level of the load applied.

  10. Trigeminal impingement syndrome: the relationship between atypical trigeminal symptoms and anteromedial disk displacement.

    PubMed

    Cascone, Piero; Fatone, Flavia Maria Graziana; Paparo, Francesco; Arangio, Paolo; Iannetti, Giorgio

    2010-07-01

    The purpose of this study was to determine if compression of the mandibular nerve and its branches could be caused by antero-medial disk displacement, resulting in atypical facial pain. Sixteen temporomandibular joints (TMJ) were dissected and injected with an autopolymerizing solution into the superior compartment, which produced an artificial capsular swelling that caused disk displacement. In all specimens, the TMJ capsule was close to the mandibular branch of the trigeminal nerve after the intracapsular injection. Thus, capsular distension or antero-medial disk displacement, as seen in various temporomandibular disorders (TMD), could result in nerve compression and facial pain symptoms. PMID:20806735

  11. Lumbar nerve root: the enigmatic eponyms.

    PubMed

    Dyck, P

    1984-01-01

    Man's quest for recognition has not escaped the physician, whose contributions to medicine perpetuate his name in print. It is a final grasp for professional immortality, which for men like Imhotep and Hippocrates, has prevailed for millennia. This fervor was particularly evident in the latter 19th century, which created a flurry of eponyms, often two or more physicians publishing the same clinical observation. This article reviews the eponym epidemic as it relates to lumbar radiculopathy. PMID:6372123

  12. Thermally drawn fibers as nerve guidance scaffolds.

    PubMed

    Koppes, Ryan A; Park, Seongjun; Hood, Tiffany; Jia, Xiaoting; Abdolrahim Poorheravi, Negin; Achyuta, Anilkumar Harapanahalli; Fink, Yoel; Anikeeva, Polina

    2016-03-01

    Synthetic neural scaffolds hold promise to eventually replace nerve autografts for tissue repair following peripheral nerve injury. Despite substantial evidence for the influence of scaffold geometry and dimensions on the rate of axonal growth, systematic evaluation of these parameters remains a challenge due to limitations in materials processing. We have employed fiber drawing to engineer a wide spectrum of polymer-based neural scaffolds with varied geometries and core sizes. Using isolated whole dorsal root ganglia as an in vitro model system we have identified key features enhancing nerve growth within these fiber scaffolds. Our approach enabled straightforward integration of microscopic topography at the scale of nerve fascicles within the scaffold cores, which led to accelerated Schwann cell migration, as well as neurite growth and alignment. Our findings indicate that fiber drawing provides a scalable and versatile strategy for producing nerve guidance channels capable of controlling direction and accelerating the rate of axonal growth. PMID:26717246

  13. Rehabilitation of the trigeminal nerve

    PubMed Central

    Iro, Heinrich; Bumm, Klaus; Waldfahrer, Frank

    2005-01-01

    When it comes to restoring impaired neural function by means of surgical reconstruction, sensory nerves have always been in the role of the neglected child when compared with motor nerves. Especially in the head and neck area, with its either sensory, motor or mixed cranial nerves, an impaired sensory function can cause severe medical conditions. When performing surgery in the head and neck area, sustaining neural function must not only be highest priority for motor but also for sensory nerves. In cases with obvious neural damage to sensory nerves, an immediate neural repair, if necessary with neural interposition grafts, is desirable. Also in cases with traumatic trigeminal damage, an immediate neural repair ought to be considered, especially since reconstructive measures at a later time mostly require for interposition grafts. In terms of the trigeminal neuralgia, commonly thought to arise from neurovascular brainstem compression, a pharmaceutical treatment is considered as the state of the art in terms of conservative therapy. A neurovascular decompression of the trigeminal root can be an alternative in some cases when surgical treatment is sought after. Besides the above mentioned therapeutic options, alternative treatments are available. PMID:22073060

  14. Modeling root reinforcement using root-failure Weibull survival function

    NASA Astrophysics Data System (ADS)

    Schwarz, M.; Giadrossich, F.; Cohen, D.

    2013-03-01

    Root networks contribute to slope stability through complicated interactions that include mechanical compression and tension. Due to the spatial heterogeneity of root distribution and the dynamic of root turnover, the quantification of root reinforcement on steep slope is challenging and consequently the calculation of slope stability as well. Although the considerable advances in root reinforcement modeling, some important aspect remain neglected. In this study we address in particular to the role of root strength variability on the mechanical behaviors of a root bundle. Many factors may contribute to the variability of root mechanical properties even considering a single class of diameter. This work presents a new approach for quantifying root reinforcement that considers the variability of mechanical properties of each root diameter class. Using the data of laboratory tensile tests and field pullout tests, we calibrate the parameters of the Weibull survival function to implement the variability of root strength in a numerical model for the calculation of root reinforcement (RBMw). The results show that, for both laboratory and field datasets, the parameters of the Weibull distribution may be considered constant with the exponent equal to 2 and the normalized failure displacement equal to 1. Moreover, the results show that the variability of root strength in each root diameter class has a major influence on the behavior of a root bundle with important implications when considering different approaches in slope stability calculation. Sensitivity analysis shows that the calibration of the tensile force and the elasticity of the roots are the most important equations, as well as the root distribution. The new model allows the characterization of root reinforcement in terms of maximum pullout force, stiffness, and energy. Moreover, it simplifies the implementation of root reinforcement in slope stability models. The realistic quantification of root reinforcement for

  15. Effects of motor and sensory nerve transplants on amount and specificity of sciatic nerve regeneration.

    PubMed

    Lago, Natalia; Rodríguez, Francisco J; Guzmán, Mónica S; Jaramillo, Jéssica; Navarro, Xavier

    2007-09-01

    Nerve regeneration after complete transection does not allow for adequate functional recovery mainly because of lack of selectivity of target reinnervation. We assessed if transplanting a nerve segment from either motor or sensory origin may improve specifically the accuracy of sensory and motor reinnervation. For this purpose, the rat sciatic nerve was transected and repaired with a silicone guide containing a predegenerated segment of ventral root (VR) or dorsal root (DR), compared to a silicone guide filled with saline. Nerve regeneration and reinnervation was assessed during 3 months by electrophysiologic and functional tests, and by nerve morphology and immunohistochemistry against choline acetyltransferase (ChAT) for labeling motor axons. Functional tests showed that reinnervation was successful in all the rats. However, the two groups with a root allotransplant reached higher degrees of reinnervation in comparison with the control group. Group VR showed the highest reinnervation of muscle targets, whereas Group DR had higher levels of sensory reinnervation than VR and saline groups. The total number of regenerated myelinated fibers was similar in the three groups, but the number of ChAT+ fibers was slightly lower in the VR group in comparison with DR and saline groups. These results indicate that a predegenerated root nerve allotransplant enhances axonal regeneration, leading to faster and higher levels of functional recovery. Although there is not clear preferential reinnervation, regeneration of motor axons is promoted at early times by a motor graft, whereas reinnervation of sensory pathways is increased by a sensory graft. PMID:17455293

  16. Visualization of nerve fibers and their relationship to peripheral nerve tumors by diffusion tensor imaging.

    PubMed

    Cage, Tene A; Yuh, Esther L; Hou, Stephanie W; Birk, Harjus; Simon, Neil G; Noss, Roger; Rao, Anuradha; Chin, Cynthia T; Kliot, Michel

    2015-09-01

    OBJECT The majority of growing and/or symptomatic peripheral nerve tumors are schwannomas and neurofibromas. They are almost always benign and can usually be resected while minimizing motor and sensory deficits if approached with the proper expertise and techniques. Intraoperative electrophysiological stimulation and recording techniques allow the surgeon to map the surface of the tumor in an effort to identify and thus avoid damaging functioning nerve fibers. Recently, MR diffusion tensor imaging (DTI) techniques have permitted the visualization of axons, because of their anisotropic properties, in peripheral nerves. The object of this study was to compare the distribution of nerve fibers as revealed by direct electrical stimulation with that seen on preoperative MR DTI. METHODS The authors conducted a retrospective chart review of patients with a peripheral nerve or nerve root tumor between March 2012 and January 2014. Diffusion tensor imaging and intraoperative data had been prospectively collected for patients with peripheral nerve tumors that were resected. Preoperative identification of the nerve fiber location in relation to the nerve tumor surface as seen on DTI studies was compared with the nerve fiber's intraoperative localization using electrophysiological stimulation and recordings. RESULTS In 23 patients eligible for study there was good correlation between nerve fiber location on DTI and its anatomical location seen intraoperatively. Diffusion tensor imaging demonstrated the relationship of nerve fibers relative to the tumor with 95.7% sensitivity, 66.7% specificity, 75% positive predictive value, and 93.8% negative predictive value. CONCLUSIONS Preoperative DTI techniques are useful in helping the peripheral nerve surgeon to both determine the risks involved in resecting a nerve tumor and plan the safest surgical approach. PMID:26323818

  17. Nerve conduction velocity

    MedlinePlus

    Nerve conduction velocity (NCV) is a test to see how fast electrical signals move through a nerve. ... normal body temperature. Being too cold slows nerve conduction. Tell your doctor if you have a cardiac ...

  18. Femoral nerve damage (image)

    MedlinePlus

    The femoral nerve is located in the leg and supplies the muscles that assist help straighten the leg. It supplies sensation ... leg. One risk of damage to the femoral nerve is pelvic fracture. Symptoms of femoral nerve damage ...

  19. Ulnar nerve damage (image)

    MedlinePlus

    The ulnar nerve originates from the brachial plexus and travels down arm. The nerve is commonly injured at the elbow because of elbow fracture or dislocation. The ulnar nerve is near the surface of the body where ...

  20. Diabetes and nerve damage

    MedlinePlus

    ... hot or cold When the nerves that control digestion are affected, you may have trouble digesting food. ... harder to control. Damage to nerves that control digestion almost always occurs in people with severe nerve ...

  1. Re-Innervation of the Bladder through End-to-Side Neurorrhaphy of Autonomic Nerve and Somatic Nerve in Rats

    PubMed Central

    Gao, Wan-sheng; Dong, Chuan-jiang; Li, Shu-qiang; Kunwar, Kiran Jang

    2012-01-01

    Abstract End-to-side neurorrhaphy is widely used in the peripheral nervous system for nerve repair; however, the application of this technique has been limited to somatic nerves. The feasibility of nerve regeneration through end-to-side neurorrhaphy between autonomic and somatic nerves with different characteristics in the peripheral nervous system is still undetermined. In this study, rats were divided into three groups for different treatments (n=10 per group). In the end-to-side neurorrhaphy group, left L6 and S1 were transected in the dura, and the distal stump of L6 ventral root was sutured to the lateral face of L4 ventral root through end-to-side coaptation. In the no repair group, the rats did not undergo neurorrhaphy. In the control group, the left L6 dorsal root and S1 roots were transected, respectively, but the L6 ventral root was kept intact. After 16 weeks, the origin and mechanism of nerve regeneration was evaluated by retrograde double labeling technique as well as histological examination and intravesical pressure measurement. Retrograde double labeling indicated that the reconstructed reflex pathway was successfully established and the primary regeneration mechanism involved axon collateral sprouting. Morphological examination and intravesical pressure measurement indicated prominent nerve regeneration and successful re-innervation of the bladder in the neurorrhaphy group, compared with the “no repair” group (p<0.05). No significant changes were observed in the histology of the donor nerve and the bilateral extensor digitorum longus muscles in the neurorrhaphy group. Nerve regeneration may be achievable for nerve repair through end-to-side neurorrhaphy between autonomic and somatic nerves without apparent impairment of donor somatic nerve. PMID:22332710

  2. Precision displacement reference system

    DOEpatents

    Bieg, Lothar F.; Dubois, Robert R.; Strother, Jerry D.

    2000-02-22

    A precision displacement reference system is described, which enables real time accountability over the applied displacement feedback system to precision machine tools, positioning mechanisms, motion devices, and related operations. As independent measurements of tool location is taken by a displacement feedback system, a rotating reference disk compares feedback counts with performed motion. These measurements are compared to characterize and analyze real time mechanical and control performance during operation.

  3. Let-7 microRNAs Regenerate Peripheral Nerve Regeneration by Targeting Nerve Growth Factor

    PubMed Central

    Li, Shiying; Wang, Xinghui; Gu, Yun; Chen, Chu; Wang, Yaxian; Liu, Jie; Hu, Wen; Yu, Bin; Wang, Yongjun; Ding, Fei; Liu, Yan; Gu, Xiaosong

    2015-01-01

    Peripheral nerve injury is a common clinical problem. Nerve growth factor (NGF) promotes peripheral nerve regeneration, but its clinical applications are limited by several constraints. In this study, we found that the time-dependent expression profiles of eight let-7 family members in the injured nerve after sciatic nerve injury were roughly similar to each other. Let-7 microRNAs (miRNAs) significantly reduced cell proliferation and migration of primary Schwann cells (SCs) by directly targeting NGF and suppressing its protein translation. Following sciatic nerve injury, the temporal change in let-7 miRNA expression was negatively correlated with that in NGF expression. Inhibition of let-7 miRNAs increased NGF secretion by primary cultured SCs and enhanced axonal outgrowth from a coculture of primary SCs and dorsal root gangalion neurons. In vivo tests indicated that let-7 inhibition promoted SCs migration and axon outgrowth within a regenerative microenvironment. In addition, the inhibitory effect of let-7 miRNAs on SCs apoptosis might serve as an early stress response to nerve injury, but this effect seemed to be not mediated through a NGF-dependent pathway. Collectively, our results provide a new insight into let-7 miRNA regulation of peripheral nerve regeneration and suggest a potential therapy for repair of peripheral nerve injury. PMID:25394845

  4. Roots Revisited.

    ERIC Educational Resources Information Center

    Hughes, Barnabas

    1998-01-01

    Offers historical information about square roots. Presents three different methods--Hero's method, visual method, and remainder method--which can be used to teach the finding of square roots and one method for determining cube roots. (ASK)

  5. [Anatomical rationale for lingual nerve injury prevention during mandibular block].

    PubMed

    Semkin, V A; Dydikin, S S; Kuzin, A V; Sogacheva, V V

    2015-01-01

    The topographic and anatomical study of lingual nerve structural features was done. It was revealed that during mandibular anesthesia possible lingual nerve injury can occur if puncture needle is lower than 1 cm. of molars occlusal surface level. The position of the lingual nerve varies withmandible movements. At the maximum open mouth lingual nerve is not mobile and is pressed against the inner surface of the mandibular ramus by the medial pterygoid muscle and the temporal muscle tendon. When closing the mouth to 1.25±0.2 cmfrom the physiological maximum, lingual nerve is displaced posteriorly from the internal oblique line of the mandible and gets mobile. On the basis of topographic and anatomic features of the lingual nervestructure the authors recommend the re-do of inferior alveolar nerve block, a semi-closed mouth position or the use the "high block techniques" (Torus anesthesia, Gow-Gates, Vazirani-Akinozi). PMID:26271698

  6. α-Synuclein pathology in the cranial and spinal nerves in Lewy body disease.

    PubMed

    Nakamura, Keiko; Mori, Fumiaki; Tanji, Kunikazu; Miki, Yasuo; Toyoshima, Yasuko; Kakita, Akiyoshi; Takahashi, Hitoshi; Yamada, Masahito; Wakabayashi, Koichi

    2016-06-01

    Accumulation of phosphorylated α-synuclein in neurons and glial cells is a histological hallmark of Lewy body disease (LBD) and multiple system atrophy (MSA). Recently, filamentous aggregations of phosphorylated α-synuclein have been reported in the cytoplasm of Schwann cells, but not in axons, in the peripheral nervous system in MSA, mainly in the cranial and spinal nerve roots. Here we conducted an immunohistochemical investigation of the cranial and spinal nerves and dorsal root ganglia of patients with LBD. Lewy axons were found in the oculomotor, trigeminal and glossopharyngeal-vagus nerves, but not in the hypoglossal nerve. The glossopharyngeal-vagus nerves were most frequently affected, with involvement in all of 20 subjects. In the spinal nerve roots, Lewy axons were found in all of the cases examined. Lewy axons in the anterior nerves were more frequent and numerous in the thoracic and sacral segments than in the cervical and lumbar segments. On the other hand, axonal lesions in the posterior spinal nerve roots appeared to increase along a cervical-to-sacral gradient. Although Schwann cell cytoplasmic inclusions were found in the spinal nerves, they were only minimal. In the dorsal root ganglia, axonal lesions were seldom evident. These findings indicate that α-synuclein pathology in the peripheral nerves is axonal-predominant in LBD, whereas it is restricted to glial cells in MSA. PMID:26563477

  7. Nerve injuries about the elbow in the athlete.

    PubMed

    Harris, Joshua D; Lintner, David M

    2014-09-01

    The athlete's elbow is a remarkable example of motion, strength, and durability. The stress placed on the elbow during sport, including the throwing motion, may lead to soft-tissue ligamentous and nerve injury. The thrower's elbow illustrates one example of possible nerve injury about the elbow in sport, related to chronic repetitive tensile and compressive stresses to the ulnar nerve associated with elbow flexion and valgus position. Besides the throwing athlete, nerve injury from high-energy direct-impact forces may also damage nerves around the elbow in contact sports. Detailed history and physical examination can often make the diagnosis of most upper extremity neuropathies. The clinician must be aware of the possibility of isolated or combined nerve injury as far proximal as the cervical nerve roots, through the brachial plexus, to the peripheral nerve terminal branches. Electrodiagnostic studies are occasionally beneficial for diagnosis with certain nerves. Nonoperative management is often successful in most elbow and upper extremity neuropathies. If conservative treatment fails, then surgical treatment should address all potentially offending structures. In the presence of medial laxity and concurrent ulnar neuritis, the medial ulnar collateral ligament warrants surgical treatment, in addition to transposition of the ulnar nerve. The morbidity of open surgical decompression of nerves in and around the elbow is potentially career threatening in the throwing athlete. This mandates an assessment of the adequacy of the nonsurgical treatment and a thorough preoperative discussion of the risks and benefits of surgery. PMID:25077754

  8. Optical measuring displacement transducers

    NASA Astrophysics Data System (ADS)

    Dich, L. Z.

    1994-09-01

    Trends in the development and production of photoelectric displacement transducers are analyzed. The technical characteristics of certain transducers are briefly presented. A table of comparisons is given, based on available information sources.

  9. Internal displacement in Burma.

    PubMed

    Lanjouw, S; Mortimer, G; Bamforth, V

    2000-09-01

    The internal displacement of populations in Burma is not a new phenomenon. Displacement is caused by numerous factors. Not all of it is due to outright violence, but much is a consequence of misguided social and economic development initiatives. Efforts to consolidate the state by assimilating populations in government-controlled areas by military authorities on the one hand, while brokering cease-fires with non-state actors on the other, has uprooted civilian populations throughout the country. Very few areas in which internally displaced persons (IDPs) are found are not facing social turmoil within a climate of impunity. Humanitarian access to IDP populations remains extremely problematic. While relatively little information has been collected, assistance has been focused on targeting accessible groups. International concern within Burma has couched the problems of displacement within general development modalities, while international attention along its borders has sought to contain displacement. With the exception of several recent initiatives, few approaches have gone beyond assistance and engaged in the prevention or protection of the displaced. PMID:11026156

  10. Dual Nerve Transfers for Restoration of Shoulder Function After Brachial Plexus Avulsion Injury.

    PubMed

    Chu, Bin; Wang, Huan; Chen, Liang; Gu, Yudong; Hu, Shaonan

    2016-06-01

    The purpose of this study was to investigate the effectiveness of shoulder function restoration by dual nerve transfers, spinal accessory nerve to the suprascapular nerve and 2 intercostal nerves to the anterior branch of the axillary nerve, in patients with shoulder paralysis that resulted from brachial plexus avulsion injury. It was a retrospective analysis to assess the impact of a variety of factors on reanimation of shoulder functions with dual nerve transfers. A total of 19 patients were included in this study. Most of these patients sustained avulsions of C5, C6, and C7 nerve roots (16 patients). Three of them had avulsions of C5 and C6 roots only. Through a posterior approach, direct coaptation of the intercostal nerves and the anterior branch of the axillary nerve was performed, along with accessory nerve transfer to the suprascapular nerve. Satisfactory shoulder function recovery (93.83° of shoulder abduction and 54.00° of external rotation on average) was achieved after a 62-month follow-up. This dual nerve transfer procedure provided us with a reliable and effective method for shoulder function reconstruction after brachial plexus root avulsion, especially C5/C6/C7 avulsion. The level of evidence is therapeutic IV. PMID:26835823

  11. Properties of postganglionic sympathetic neurons with axons in phrenic nerve.

    PubMed

    Bałkowiec, A; Szulczyk, P

    1992-06-01

    The aim of the study was to test the reflex and resting properties of postganglionic sympathetic neurons with axons located in the right phrenic nerve. The experiments have been performed on chloralose-anesthetized cats with both vago-aortic nerves cut. The somata or the postganglionic sympathetic neurons were located in the stellate ganglion. Axons of these neurons passed through the upper and lower phrenic nerve roots and through the phrenic nerve itself. The presence of cardiac and respiratory rhythmicities was detected in the activity of the phrenic postganglionic sympathetic neurons. Hyperventilation, which abolished burst discharges of the phrenic nerve, decreased the sympathetic activity by 14%. Systemic hypoxia (ventilating the animals for 2 min with 8% O2 in N2) increased the sympathetic activity threefold. The results of our experiments suggest that axons of the sympathetic neurons located in the right phrenic nerve could possibly be diaphragmatic muscle vasoconstrictors. PMID:1615229

  12. Nerve conduction velocity

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003927.htm Nerve conduction velocity To use the sharing features on this page, please enable JavaScript. Nerve conduction velocity (NCV) is a test to see how ...

  13. Assessing nerves in leprosy.

    PubMed

    Garbino, José Antonio; Heise, Carlos Otto; Marques, Wilson

    2016-01-01

    Leprosy neuropathy is dependent on the patient's immune response and expresses itself as a focal or multifocal neuropathy with asymmetric involvement. Leprosy neuropathy evolves chronically but recurrently develops periods of exacerbation during type 1 or type 2 reactions, leading to acute neuropathy. Nerve enlargement leading to entrapment syndromes is also a common manifestation. Pain may be either of inflammatory or neuropathic origin. A thorough and detailed evaluation is mandatory for adequate patient follow-up, including nerve palpation, pain assessment, graded sensory mapping, muscle power testing, and autonomic evaluation. Nerve conduction studies are a sensitive tool for nerve dysfunction, including new lesions during reaction periods or development of entrapment syndromes. Nerve ultrasonography is also a very promising method for nerve evaluation in leprosy. The authors propose a composite nerve clinical score for nerve function assessment that can be useful for longitudinal evaluation. PMID:26773623

  14. Ulnar nerve damage (image)

    MedlinePlus

    ... arm. The nerve is commonly injured at the elbow because of elbow fracture or dislocation. The ulnar nerve is near ... surface of the body where it crosses the elbow, so prolonged pressure on the elbow or entrapment ...

  15. Nerve Injuries in Athletes.

    ERIC Educational Resources Information Center

    Collins, Kathryn; And Others

    1988-01-01

    Over a two-year period this study evaluated the condition of 65 athletes with nerve injuries. These injuries represent the spectrum of nerve injuries likely to be encountered in sports medicine clinics. (Author/MT)

  16. Radial nerve dysfunction (image)

    MedlinePlus

    The radial nerve travels down the arm and supplies movement to the triceps muscle at the back of the upper arm. ... the wrist and hand. The usual causes of nerve dysfunction are direct trauma, prolonged pressure on the ...

  17. Tibial nerve dysfunction

    MedlinePlus

    ... a loss of movement or sensation in the foot from damage to the tibial nerve. ... Tibial nerve dysfunction is an unusual form of peripheral ... the calf and foot muscles. A problem in function with a single ...

  18. Degenerative Nerve Diseases

    MedlinePlus

    Degenerative nerve diseases affect many of your body's activities, such as balance, movement, talking, breathing, and heart function. Many ... viruses. Sometimes the cause is not known. Degenerative nerve diseases include Alzheimer's disease Amyotrophic lateral sclerosis Friedreich's ...

  19. Radial nerve dysfunction

    MedlinePlus

    ... nerve leads to problems with movement in the arm and wrist and with sensation in the back of the arm or hand. ... to the radial nerve, which travels down the arm and controls movement of the triceps muscle at ...

  20. Abducens nerve palsy after schwannoma resection.

    PubMed

    Bobbio, Antonio; Hamelin-Canny, Emelyne; Roche, Nicolas; Taillia, Herve; Alifano, Marco

    2015-02-01

    Tumors of the posterior mediastinum are mostly neurogenic and could involve the intervertebral foramen and the medullary canal. We describe the case of a patient who underwent surgery for a nerve sheet tumor originating at the level of the right second neural root. Resection was associated with an incidental dural tear and cerebrospinal fluid leak that was promptly repaired. One week after surgery, horizontal diplopia occurred. A palsy of the left abducens nerve secondary to intracranial hypotension was diagnosed. We present the pathogenic cascade leading to this ocular complication after posterior mediastinal surgery. The surgical techniques to prevent this complication are discussed. PMID:25639411

  1. Laryngeal nerve damage

    MedlinePlus

    Laryngeal nerve damage is injury to one or both of the nerves that are attached to the voice box. ... Injury to the laryngeal nerves is uncommon. When it does occur, it can be from: A complication of neck or chest surgery (especially thyroid, lung, ...

  2. [Incarcerated epitrochlear fracture with a cubital nerve injury].

    PubMed

    Moril-Peñalver, L; Pellicer-Garcia, V; Gutierrez-Carbonell, P

    2013-01-01

    Injuries of the medial epicondyle are relatively common, mostly affecting children between 7 and 15 years. The anatomical characteristics of this apophysis can make diagnosis difficult in minimally displaced fractures. In a small percentage of cases, the fractured fragment may occupy the retroepitrochlear groove. The presence of dysesthesias in the territory of the ulnar nerve requires urgent open reduction of the incarcerated fragment. A case of a seven-year-old male patient is presented, who required surgical revision due to a displaced medial epicondyle fracture associated with ulnar nerve injury. A review of the literature is also made. PMID:24071050

  3. Water displacement mercury pump

    DOEpatents

    Nielsen, M.G.

    1984-04-20

    A water displacement mercury pump has a fluid inlet conduit and diffuser, a valve, a pressure cannister, and a fluid outlet conduit. The valve has a valve head which seats in an opening in the cannister. The entire assembly is readily insertable into a process vessel which produces mercury as a product. As the mercury settles, it flows into the opening in the cannister displacing lighter material. When the valve is in a closed position, the pressure cannister is sealed except for the fluid inlet conduit and the fluid outlet conduit. Introduction of a lighter fluid into the cannister will act to displace a heavier fluid from the cannister via the fluid outlet conduit. The entire pump assembly penetrates only a top wall of the process vessel, and not the sides or the bottom wall of the process vessel. This insures a leak-proof environment and is especially suitable for processing of hazardous materials.

  4. Optical displacement sensor

    DOEpatents

    Carr, Dustin W.

    2008-04-08

    An optical displacement sensor is disclosed which uses a vertical-cavity surface-emitting laser (VCSEL) coupled to an optical cavity formed by a moveable membrane and an output mirror of the VCSEL. This arrangement renders the lasing characteristics of the VCSEL sensitive to any movement of the membrane produced by sound, vibrations, pressure changes, acceleration, etc. Some embodiments of the optical displacement sensor can further include a light-reflective diffractive lens located on the membrane or adjacent to the VCSEL to control the amount of lasing light coupled back into the VCSEL. A photodetector detects a portion of the lasing light from the VCSEL to provide an electrical output signal for the optical displacement sensor which varies with the movement of the membrane.

  5. Polymerase chain displacement reaction.

    PubMed

    Harris, Claire L; Sanchez-Vargas, Irma J; Olson, Ken E; Alphey, Luke; Fu, Guoliang

    2013-02-01

    Quantitative PCR assays are now the standard method for viral diagnostics. These assays must be specific, as well as sensitive, to detect the potentially low starting copy number of viral genomic material. We describe a new technique, polymerase chain displacement reaction (PCDR), which uses multiple nested primers in a rapid, capped, one-tube reaction that increases the sensitivity of normal quantitative PCR (qPCR) assays. Sensitivity was increased by approximately 10-fold in a proof-of-principle test on dengue virus sequence. In PCDR, when extension occurs from the outer primer, it displaces the extension strand produced from the inner primer by utilizing a polymerase that has strand displacement activity. This allows a greater than 2-fold increase of amplification product for each amplification cycle and therefore increased sensitivity and speed over conventional PCR. Increased sensitivity in PCDR would be useful in nucleic acid detection for viral diagnostics. PMID:23384180

  6. Water displacement mercury pump

    DOEpatents

    Nielsen, Marshall G.

    1985-01-01

    A water displacement mercury pump has a fluid inlet conduit and diffuser, a valve, a pressure cannister, and a fluid outlet conduit. The valve has a valve head which seats in an opening in the cannister. The entire assembly is readily insertable into a process vessel which produces mercury as a product. As the mercury settles, it flows into the opening in the cannister displacing lighter material. When the valve is in a closed position, the pressure cannister is sealed except for the fluid inlet conduit and the fluid outlet conduit. Introduction of a lighter fluid into the cannister will act to displace a heavier fluid from the cannister via the fluid outlet conduit. The entire pump assembly penetrates only a top wall of the process vessel, and not the sides or the bottom wall of the process vessel. This insures a leak-proof environment and is especially suitable for processing of hazardous materials.

  7. Chromo-fluorogenic BODIPY-complexes for selective detection of V-type nerve agent surrogates.

    PubMed

    Barba-Bon, Andrea; Costero, Ana María; Gil, Salvador; Sancenón, Félix; Martínez-Máñez, Ramón

    2014-11-11

    Two new Eu(3+) and Au(3+) BODIPY-complexes capable of chromo-fluorogenically detecting micromolar concentrations of V-type nerve agent surrogates by a simple displacement assay are described. PMID:25233370

  8. High Median Nerve Injuries.

    PubMed

    Isaacs, Jonathan; Ugwu-Oju, Obinna

    2016-08-01

    The median nerve serves a crucial role in extrinsic and intrinsic motor and sensory function to the radial half of the hand. High median nerve injuries, defined as injuries proximal to the anterior interosseous nerve origin, therefore typically result in significant functional loss prompting aggressive surgical management. Even with appropriate recognition and contemporary nerve reconstruction, however, motor and sensory recovery may be inadequate. With isolated persistent high median nerve palsies, a variety of available tendon transfers can improve key motor functions and salvage acceptable use of the hand. PMID:27387077

  9. Nerve growth factor released from a novel PLGA nerve conduit can improve axon growth

    NASA Astrophysics Data System (ADS)

    Lin, Keng-Min; Shea, Jill; Gale, Bruce K.; Sant, Himanshu; Larrabee, Patti; Agarwal, Jay

    2016-04-01

    Nerve injury can occur due to penetrating wounds, compression, traumatic stretch, and cold exposure. Despite prompt repair, outcomes are dismal. In an attempt to help resolve this challenge, in this work, a poly-lactic-co-glycolic acid (PLGA) nerve conduit with associated biodegradable drug reservoir was designed, fabricated, and tested. Unlike current nerve conduits, this device is capable of fitting various clinical scenarios by delivering different drugs without reengineering the whole system. To demonstrate the potential of this device for nerve repair, a series of experiments were performed using nerve growth factor (NGF). First, an NGF dosage curve was developed to determine the minimum NGF concentration for optimal axonal outgrowth on chick dorsal root ganglia (DRG) cells. Next, PLGA devices loaded with NGF were evaluated for sustained drug release and axon growth enhancement with the released drug. A 20 d in vitro release test was conducted and the nerve conduit showed the ability to meet and maintain the minimum NGF requirement determined previously. Bioactivity assays of the released NGF showed that drug released from the device between the 15th and 20th day could still promote axon growth (76.6-95.7 μm) in chick DRG cells, which is in the range of maximum growth. These novel drug delivery conduits show the ability to deliver NGF at a dosage that efficiently promotes ex vivo axon growth and have the potential for in vivo application to help bridge peripheral nerve gaps.

  10. [Ganglia of peripheral nerves].

    PubMed

    Tatagiba, M; Penkert, G; Samii, M

    1993-01-01

    The authors present two different types of ganglion affecting the peripheral nerves: extraneural and intraneural ganglion. Compression of peripheral nerves by articular ganglions is well known. The surgical management involves the complete removal of the lesion with preservation of most nerve fascicles. Intraneural ganglion is an uncommon lesion which affects the nerve diffusely. The nerve fascicles are usually intimately involved between the cysts, making complete removal of all cysts impossible. There is no agreement about the best surgical management to be applied in these cases. Two possibilities are available: opening of the epineural sheath lengthwise and pressing out the lesion; or resection of the affected part of the nerve and performing a nerve reconstruction. While in case of extraneural ganglion the postoperative clinical evolution is very favourable, only long follow up studies will reveal in case of intraneural ganglion the best surgical approach. PMID:8128785

  11. Melanotic schwannoma of the L5 root.

    PubMed

    Güzel, Ebru; Er, Uygur; Güzel, Aslan; Toktaş, Zafer; Yapıcıer, Özlem

    2016-06-01

    Melanotic neoplasm of the central nervous system is rare and the majority of them are metastatic. Melanotic schwannoma (MS) is an unusual variant of nerve sheath neoplasm accounting for less than 1% of primary nerve sheath tumors. A case involving a 36-year-old man with MS at the L5 root is presented. Surgery, differential diagnosis, radiology, histology, and treatment of this rare entity are discussed. PMID:26969197

  12. Assessment of nerve morphology in nerve activation during electrical stimulation

    NASA Astrophysics Data System (ADS)

    Gomez-Tames, Jose; Yu, Wenwei

    2013-10-01

    The distance between nerve and stimulation electrode is fundamental for nerve activation in Transcutaneous Electrical Stimulation (TES). However, it is not clear the need to have an approximate representation of the morphology of peripheral nerves in simulation models and its influence in the nerve activation. In this work, depth and curvature of a nerve are investigated around the middle thigh. As preliminary result, the curvature of the nerve helps to reduce the simulation amplitude necessary for nerve activation from far field stimulation.

  13. Square Root +

    ERIC Educational Resources Information Center

    Frederiksen, John G.

    1969-01-01

    A rational presentation of the so-called long division method for extracting the square root of a number. Diagrams are used to show relationship of this technique to the binomial theorem. Presentation exposes student to many facets of mathematics in addition to the mechanics of funding square root and cube root. Geometry, algebraic statements,…

  14. The distribution of nerves in human deciduous and permanent teeth.

    PubMed

    Itoh, K

    1976-11-01

    Human permanent teeth without caries, obtained from 10-16 year old males and females and noncarious human deciduous teeth in which roots remained intact or were only poorly resorbed, were studied histologically. The distribution of sensory nerves in deciduous teeth were compared with that in permanent teeth by means of the silver-nitrate technique. 1. In radicular pulp, the sensory nerve fiber bundles accompany blood vessels in the axial area and several nerve single-fibers occur in the peripheral area of the pulp. 2. The subodontoblastic nerve plexus is formed in or beneath the cell-rich zone of the coronal pulp, and further, the marginal nerve plexus is built up near the pulpo-predentinal border. 3. The nerve fibers entering the predentin can be classified into 3 types by their courses. In the first type, nerve fibers pass directly toward the calcification front along the dentinal tubules in the predentin. In the second type, nerve fibers run obliquely or transversely in the predentin. The transversal fibers form a plexus-like structure by dividing and interlacing at various levels of predentin. The third type nerve fibers pass along the dentinal tubules in the predentin and, after reaching the predentino-dentinal border, reverse the odontoblast layer, thus forming a looped course. 4. There is no essential difference between the nerve supply in the deciduous and in the permanent teeth, but the nerves in the deciduous teeth are less dense in distribution and lower in amount than in the permanent teeth. Moreover, a typical marginal nerve plexus, which occurs constantly in the permanent teeth, is only occasionally found in the deciduous teeth; and no nerve fiber was observed to penetrate into the calcified dentin in the deciduous teeth. This finding seems to account for the fact that the deciduous teeth are less sensitive than their permanent successors. PMID:798562

  15. Controlled Delivery of FK506 to Improve Nerve Regeneration.

    PubMed

    Labroo, Pratima; Ho, Scott; Sant, Himanshu; Shea, Jill; Gale, Bruce K; Agarwal, Jay

    2016-09-01

    Autologous nerve grafts are the current "gold standard" for repair of large nerve gaps. However, they cause morbidity at the donor nerve site, only a limited amount of nerve can be harvested, and there is the potential for mismatches in size and fascicular patterns between the nerve stumps and the graft. Nerve conduits are a promising alternative to autografts and can act as guidance cues for the regenerating axons and allow for tension free bridging, without the need to harvest donor nerve. Separately, FK506, and FDA-approved small molecule, has been shown to enhance axon growth and peripheral nerve regeneration. This article describes the design of a novel drug delivery apparatus integrated with a poly lactic-co-glycolic acid (PLGA)-based nerve guide conduit for controlled local delivery of FK506. An FK506 dosage curve was acquired to determine the minimum in vitro concentration for optimal axonal outgrowth of dorsal root ganglion (DRG) cells, then PLGA devices were designed and tested in a diffusion chamber, and finally the bioactivity of the released media was evaluated by measuring axon growth in DRG cells exposed to the media for 72 h. The combined drug delivery nerve guide was able to release FK506 for 20 days at concentrations (1-20 ng/mL) that were shown to enhance DRG axon growth. Furthermore, the released FK506 was bioactive and able to enhance DRG axon growth. The combined drug delivery nerve guide can release FK506 for extended periods of time and enhance axon growth, and has the potential to improve nerve regeneration after a peripheral nerve injury. PMID:27058050

  16. Root Hairs

    PubMed Central

    Grierson, Claire; Nielsen, Erik; Ketelaarc, Tijs; Schiefelbein, John

    2014-01-01

    Roots hairs are cylindrical extensions of root epidermal cells that are important for acquisition of nutrients, microbe interactions, and plant anchorage. The molecular mechanisms involved in the specification, differentiation, and physiology of root hairs in Arabidopsis are reviewed here. Root hair specification in Arabidopsis is determined by position-dependent signaling and molecular feedback loops causing differential accumulation of a WD-bHLH-Myb transcriptional complex. The initiation of root hairs is dependent on the RHD6 bHLH gene family and auxin to define the site of outgrowth. Root hair elongation relies on polarized cell expansion at the growing tip, which involves multiple integrated processes including cell secretion, endomembrane trafficking, cytoskeletal organization, and cell wall modifications. The study of root hair biology in Arabidopsis has provided a model cell type for insights into many aspects of plant development and cell biology. PMID:24982600

  17. The Furcal Nerve Revisited

    PubMed Central

    Dabke, Harshad V.

    2014-01-01

    Atypical sciatica and discrepancy between clinical presentation and imaging findings is a dilemma for treating surgeon in management of lumbar disc herniation. It also constitutes ground for failed back surgery and potential litigations thereof. Furcal nerve (Furcal = forked) is an independent nerve with its own ventral and dorsal branches (rootlets) and forms a link nerve that connects lumbar and sacral plexus. Its fibers branch out to be part of femoral and obturator nerves in-addition to the lumbosacral trunk. It is most commonly found at L4 level and is the most common cause of atypical presentation of radiculopathy/sciatica. Very little is published about the furcal nerve and many are unaware of its existence. This article summarizes all the existing evidence about furcal nerve in English literature in an attempt to create awareness and offer insight about this unique entity to fellow colleagues/professionals involved in spine care. PMID:25317309

  18. Sciatic nerve injection injury.

    PubMed

    Jung Kim, Hyun; Hyun Park, Sang

    2014-06-11

    Nerve injury is a common complication following intramuscular injection and the sciatic nerve is the most frequently affected nerve, especially in children, the elderly and underweight patients. The neurological presentation may range from minor transient pain to severe sensory disturbance and motor loss with poor recovery. Management of nerve injection injury includes drug treatment of pain, physiotherapy, use of assistive devices and surgical exploration. Early recognition of nerve injection injury and appropriate management are crucial in order to reduce neurological deficit and to maximize recovery. Sciatic nerve injection injury is a preventable event. Total avoidance of intramuscular injection is recommended if other administration routes can be used. If the injection has to be administered into the gluteal muscle, the ventrogluteal region (gluteal triangle) has a more favourable safety profile than the dorsogluteal region (the upper outer quadrant of the buttock). PMID:24920643

  19. The photoelectric displacement converter

    NASA Astrophysics Data System (ADS)

    Dragoner, Valeriu V.

    2005-02-01

    In the article are examined questions of constructing photoelectric displacement converter satisfying demands that are stated above. Converter has channels of approximate and precise readings. The approximate reading may be accomplished either by the method of reading from a code mask or by the method of the consecutive calculation of optical scale gaps number. Phase interpolator of mouar strips" gaps is determined as a precise measuring. It is shown mathematical model of converter that allow evaluating errors and operating speed of conversion.

  20. Tunable beam displacer

    SciTech Connect

    Salazar-Serrano, Luis José; Valencia, Alejandra; Torres, Juan P.

    2015-03-15

    We report the implementation of a tunable beam displacer, composed of a polarizing beam splitter (PBS) and two mirrors, that divides an initially polarized beam into two parallel beams whose separation can be continuously tuned. The two output beams are linearly polarized with either vertical or horizontal polarization and no optical path difference is introduced between them. The wavelength dependence of the device as well as the maximum separation between the beams achievable is limited mainly by the PBS characteristics.

  1. RTV 21 Displacements

    SciTech Connect

    Kurita, C.H.; /Fermilab

    1987-02-04

    A seal is needed for the cover of the Nitrogen Test Vessel in order to prevent leakage of the N{sub 2} gas. This seal is to be molded out of RTV 21. In this experiment, the Modulus of Elasticity of the RTV was sought after, and the displacements of the RTV due to various stresses were measured to see if they were large enough to provide a tight seal between the vessel and its cover.

  2. Alginate as a displacer for protein displacement chromatography.

    PubMed

    Chen, G; Scouten, W H

    1996-01-01

    Alginate use in displacement chromatography as a displacer has been studied. The experiments showed that untreated alginate is the basis of potential displacer for displacement chromatography, but needs to be cleaved into smaller chains. Alginate treated with ultrasound, which cleaves alginate into shorter polysaccharide chains, gave better displacement than untreated alginate, while alginate subjected to limited acid hydrolysis gave the best results in displacement chromatography. It was found that the mixture of ovalbumin and beta-lactoglobulin separated well, and several components of ovalbumin were also separated and purified when alginate hydrolysate was used as a displacer. beta-Lactoglobulins A and B, which have the same molecular weight and differ in isoelectric point by only 0.1 pH units, were displaced from Q-Sepharose by alginate hydrolysate. PMID:9174919

  3. Optical stimulation of peripheral nerves in vivo

    NASA Astrophysics Data System (ADS)

    Wells, Jonathon D.

    This dissertation documents the emergence and validation of a new clinical tool that bridges the fields of biomedical optics and neuroscience. The research herein describes an innovative method for direct neurostimulation with pulsed infrared laser light. Safety and effectiveness of this technique are first demonstrated through functional stimulation of the rat sciatic nerve in vivo. The Holmium:YAG laser (lambda = 2.12 mum) is shown to operate at an optimal wavelength for peripheral nerve stimulation with advantages over standard electrical neural stimulation; including contact-free stimulation, high spatial selectivity, and lack of a stimulation artifact. The underlying biophysical mechanism responsible for transient optical nerve stimulation appears to be a small, absorption driven thermal gradient sustained at the axonal layer of nerve. Results explicitly prove that low frequency optical stimulation can reliably stimulate without resulting in tissue thermal damage. Based on the positive results from animal studies, these optimal laser parameters were utilized to move this research into the clinic with a combined safety and efficacy study in human subjects undergoing selective dorsal rhizotomy. The clinical Holmium:YAG laser was used to effectively stimulate human dorsal spinal roots and elicit functional muscle responses recorded during surgery without evidence of nerve damage. Overall these results predict that this technology can be a valuable clinical tool in various neurosurgical applications.

  4. Peripheral nerve regeneration and neurotrophic factors

    PubMed Central

    TERENGHI, GIORGIO

    1999-01-01

    The role of neurotrophic factors in the maintenance and survival of peripheral neuronal cells has been the subject of numerous studies. Administration of exogenous neurotrophic factors after nerve injury has been shown to mimic the effect of target organ-derived trophic factors on neuronal cells. After axotomy and during peripheral nerve regeneration, the neurotrophins NGF, NT-3 and BDNF show a well defined and selective beneficial effect on the survival and phenotypic expression of primary sensory neurons in dorsal root ganglia and of motoneurons in spinal cord. Other neurotrophic factors such as CNTF, GDNF and LIF also exert a variety of actions on neuronal cells, which appear to overlap and complement those of the neurotrophins. In addition, there is an indirect contribution of GGF to nerve regeneration. GGF is produced by neurons and stimulates proliferation of Schwann cells, underlining the close interaction between neuronal and glial cells during peripheral nerve regeneration. Different possibilities have been investigated for the delivery of growth factors to the injured neurons, in search of a suitable system for clinical applications. The studies reviewed in this article show the therapeutic potential of neurotrophic factors for the treatment of peripheral nerve injury and for neuropathies. PMID:10227662

  5. Endoscopic Facial Nerve Surgery.

    PubMed

    Marchioni, Daniele; Soloperto, Davide; Rubini, Alessia; Nogueira, João Flávio; Badr-El-Dine, Mohamed; Presutti, Livio

    2016-10-01

    Tympanic facial nerve segment surgery has been traditionally performed using microscopic approaches, but currently, exclusive endoscopic approaches have been performed for traumatic, neoplastic, or inflammatory diseases, specially located at the geniculate ganglion, greater petrosal nerve, and second tract of the facial nerve, until the second genu. The tympanic segment of the facial nerve can be reached and visualized using an exclusive transcanal endoscopic approach, even in poorly accessible regions such as the second genu and geniculate ganglion, avoiding mastoidectomy, bony demolition, and meningeal or cerebral lobe tractions, with low complication rates using a minimally invasive surgical route. PMID:27468633

  6. Root reinforcement of soils under compression

    NASA Astrophysics Data System (ADS)

    Schwarz, M.; Rist, A.; Cohen, D.; Giadrossich, F.; Egorov, P.; Büttner, D.; Stolz, M.; Thormann, J.-J.

    2015-10-01

    It is well recognized that roots reinforce soils and that the distribution of roots within vegetated hillslopes strongly influences the spatial distribution of soil strength. Previous studies have focussed on the contribution of root reinforcement under conditions of tension or shear. However, no systematic investigation into the contribution of root reinforcement to soils experiencing compression, such as the passive Earth forces at the toe of a landslide, is found in the literature. An empirical-analytical model (CoRoS) for the quantification of root reinforcement in soils under compression is presented and tested against experimental data. The CoRoS model describes the force-displacement behavior of compressed, rooted soils and can be used to provide a framework for improving slope stability calculations. Laboratory results showed that the presence of 10 roots with diameters ranging from 6 to 28 mm in a rectangular soil profile 0.72 m by 0.25 m increased the compressive strength of the soil by about 40% (2.5 kN) at a displacement of 0.05 m, while the apparent stiffness of the rooted soil was 38% higher than for root-free soil. The CoRoS model yields good agreement with experimentally determined values of maximum reinforcement force and compression force as a function of displacement. These results indicate that root reinforcement under compression has a major influence on the mechanical behavior of soil and that the force-displacement behavior of roots should be included in analysis of the compressive regimes that commonly are present in the toe of landslides.

  7. Nerve ultrasound for differentiation between amyotrophic lateral sclerosis and multifocal motor neuropathy.

    PubMed

    Grimm, Alexander; Décard, Bernhard F; Athanasopoulou, Ioanna; Schweikert, Kathi; Sinnreich, Michael; Axer, Hubertus

    2015-01-01

    Ultrasound is useful for non-invasive visualization of focal nerve pathologies probably resulting from demyelination, remyelination, edema or inflammation. In patients with progressive muscle weakness, differentiation between multifocal motor neuropathy (MMN) and amyotrophic lateral sclerosis (ALS) is essential regarding therapy and prognosis. Therefore, the objective of this study was to investigate whether nerve ultrasound can differentiate between ALS and MMN. Systematic ultrasound measurements of peripheral nerves and the 6th cervical nerve root (C6) were performed in 17 patients with ALS, in 8 patients with MMN and in 28 healthy controls. Nerve conduction studies of corresponding nerves were undertaken in MMN and ALS patients. Electromyography was performed in ALS patients according to revised El-Escorial criteria. ANOVA and unpaired t test with Bonferroni correction revealed significant differences in cross-sectional areas (CSA) of different nerves and C6 diameter between the groups. Nerve enlargement was found significantly more frequently in MMN than in other groups (p < 0.001). Receiver operating characteristics analysis revealed detection of enlarged nerves/roots in at least four measurement points to serve as a good marker to differentiate MMN from ALS with a sensitivity of 87.5% and a specificity of 94.1%. Ultrasonic focal nerve enlargement in MMN was often not colocalized with areas of conduction blocks found in nerve conduction studies. Systematic ultrasound measurements in different nerves and nerve roots are valuable for detecting focal nerve enlargement in MMN, generally not found in ALS and thus could serve as a diagnostic marker to differentiate between both entities in addition to electrodiagnostic studies. PMID:25626722

  8. Propagation Speed in Myelinated Nerve

    PubMed Central

    Hardy, W. L.

    1973-01-01

    The Hodgkin-Huxley (H.H.) equations modified by Dodge for Rana pipiens myelinated nerve have been solved to determine how well the theory predicts the effects of changes of temperature and [Na+]0 on propagation. Conduction speed θ was found to have an approximately exponential dependence on temperature as was found experimentally, but the theoretical temperature coefficient (Q10) was low; 1.5 compared with the experimental finding of 2.95. θ was found to be a linear function of log ([Na+]0) in contrast to the experimental finding of a square root dependence on [Na+]0. θ is 50% greater at one-fourth normal [Na+]0 than the theory predicts. The difference between the theoretical θ([Na+]0) and the experimental θ([Na+]0) is probably due to an imprecisely known variation of parameters and not to a fundamental inadequacy of the theory. PMID:4542941

  9. An electromechanical displacement transducer

    NASA Astrophysics Data System (ADS)

    Villiers, Marius; Mahboob, Imran; Nishiguchi, Katsuhiko; Hatanaka, Daiki; Fujiwara, Akira; Yamaguchi, Hiroshi

    2016-08-01

    Two modes of an electromechanical resonator are coupled through the strain inside the structure with a cooperativity as high as 107, a state-of-the-art value for purely mechanical systems, which enables the observation of normal-mode splitting. This coupling is exploited to transduce the resonator’s fundamental mode into the bandwidth of the second flexural mode, which is 1.4 MHz higher in frequency. Thus, an all-mechanical heterodyne detection scheme is implemented that can be developed into a high-precision displacement sensor.

  10. Evolution of rapid nerve conduction.

    PubMed

    Castelfranco, Ann M; Hartline, Daniel K

    2016-06-15

    Rapid conduction of nerve impulses is a priority for organisms needing to react quickly to events in their environment. While myelin may be viewed as the crowning innovation bringing about rapid conduction, the evolution of rapid communication mechanisms, including those refined and enhanced in the evolution of myelin, has much deeper roots. In this review, a sequence is traced starting with diffusional communication, followed by transport-facilitated communication, the rise of electrical signaling modalities, the invention of voltage-gated channels and "all-or-none" impulses, the emergence of elongate nerve axons specialized for communication and their fine-tuning to enhance impulse conduction speeds. Finally within the evolution of myelin itself, several innovations have arisen and have been interactively refined for speed enhancement, including the addition and sealing of layers, their limitation by space availability, and the optimization of key parameters: channel density, lengths of exposed nodes and lengths of internodes. We finish by suggesting several design principles that appear to govern the evolution of rapid conduction. This article is part of a Special Issue entitled SI: Myelin Evolution. PMID:26879248

  11. Synthesis of finite displacements and displacements in continental margins

    NASA Technical Reports Server (NTRS)

    Speed, R. C.; Elison, M. W.; Heck, F. R.; Russo, R. M.

    1988-01-01

    The scope of the project is the analysis of displacement-rate fields in the transitional regions between cratonal and oceanic lithospheres over Phanerozoic time (last 700 ma). Associated goals are an improved understanding of range of widths of major displacement zones; the partition of displacement gradients and rotations with position and depth in such zones; the temporal characteristics of such zones-the steadiness, episodicity, and duration of uniform versus nonunifrom fields; and the mechanisms and controls of the establishment and kinematics of displacement zones. The objective is to provide a context of time-averaged kinematics of displacement zones. The initial phase is divided topically among the methodology of measurement and reduction of displacements in the lithosphere and the preliminary analysis from geologic and other data of actual displacement histories from the Cordillera, Appalachians, and southern North America.

  12. Optic Nerve Decompression

    MedlinePlus

    ... canals). The optic nerve is the “nerve of vision” and extends from the brain, through your skull, and into your eye. A ... limited to, the following: loss of vision, double vision, inadequate ... leakage of brain fluid (CSF), meningitis, nasal bleeding, infection of the ...

  13. Inferior alveolar nerve repositioning.

    PubMed

    Louis, P J

    2001-09-01

    Nerve repositioning is a viable alternative for patients with an atrophic edentulous posterior mandible. Patients, however, should be informed of the potential risks of neurosensory disturbance. Documentation of the patient's baseline neurosensory function should be performed with a two-point discrimination test or directional brush stroke test preoperatively and postoperatively. Recovery of nerve function should be expected in 3 to 6 months. The potential for mandibular fracture when combining nerve repositioning with implant placement also should be discussed with the patient. This can be avoided by minimizing the amount of buccal cortical plate removal during localization of the nerve and maintaining the integrity of the inferior cortex of the mandible. Additionally, avoid overseating the implant, thus avoiding stress along the inferior border of the mandible. The procedure does allow for the placement of longer implants, which should improve implant longevity. Patients undergoing this procedure have expressed overall satisfaction with the results. Nerve repositioning also can be used to preserve the inferior alveolar nerve during resection of benign tumors or cysts of the mandible. This procedure allows the surgeon to maintain nerve function in situations in which the nerve would otherwise have to be resected. PMID:11665379

  14. Intraoperative vagal nerve monitoring.

    PubMed

    Leonetti, J P; Jellish, W S; Warf, P; Hudson, E

    1996-08-01

    A variety of benign and malignant neoplasms occur in the superior cervical neck, parapharyngeal space or the infratemporal fossa. The surgical resection of these lesions may result in postoperative iatrogenic injury to the vagus nerve with associated dysfunctional swallowing and airway protection. Anatomic and functional preservation of this critical cranial nerve will contribute to a favorable surgical outcome. Fourteen patients with tumors of the cervical neck or adjacent skull base underwent intraoperative vagal nerve monitoring in an attempt to preserve neural integrity following tumor removal. Of the 11 patients with anatomically preserved vagal nerves in this group, seven patients had normal vocal cord mobility following surgery and all 11 patients demonstrated normal vocal cord movement by six months. In an earlier series of 23 patients with tumors in the same region who underwent tumor resection without vagal nerve monitoring, 18 patients had anatomically preserved vagal nerves. Within this group, five patients had normal vocal cord movement at one month and 13 patients demonstrated normal vocal cord movement at six months. This paper will outline a technique for intraoperative vagal nerve monitoring utilizing transcricothyroid membrane placement of bipolar hook-wire electrodes in the vocalis muscle. Our results with the surgical treatment of cervical neck and lateral skull base tumors for patients with unmonitored and monitored vagal nerves will be outlined. PMID:8828272

  15. Distal median nerve dysfunction

    MedlinePlus

    ... Names Neuropathy - distal median nerve Images Central nervous system and peripheral nervous system References Jarvik JG, Comstock BA, Kliot M, et al. Surgery versus non-surgical therapy for carpal tunnel syndrome: a randomized ... D. Disorders of peripheral nerves. In: Daroff RB, Fenichel GM, Jankovic J, ...

  16. Anterior Displacement of the Geniculate Ganglion.

    PubMed

    Tachibana, Tomoyasu; Orita, Yorihisa; Nishizaki, Kazunori

    2016-04-01

    We present the case of a 34-year-old Japanese woman with cholesteatoma of the middle ear. During the operation, this patient showed an unusual position of the geniculate ganglion. We reviewed the computed tomography (CT) images targeting the ear of the present case after the operation. We found that the shortest ranges from the ampullated end of the superior semicircular canal to the geniculate ganglion fossa were 5.1 mm on both sides. We did not find any cases with obvious dislocation of the geniculate ganglion among the 67 cases for which we had performed tympanoplasty. Displacement of the geniculate ganglion is either extremely rare or typically unnoticed because this abnormality is asymptomatic. We speculated that the unusual position of the geniculate ganglion was due to an incomplete development of the tympanic tegmen. When surgical treatment such as decompression of the facial nerve or tympanoplasty is performed, close attention should always be paid to the anatomy of the facial nerve from the labyrinthine segment to the geniculate ganglion. In the present case, although connective tissues existed around the anterior epitympanic recess, we left this lesion to avoid iatrogenic facial palsy. PMID:27340996

  17. Sensitivity of the "Root Bundle Model" to root mechanical properties and root distribution: Implication for shallow landslide stability.

    NASA Astrophysics Data System (ADS)

    Schwarz, Massimiliano; Giadrossich, Filippo; Cohen, Denis

    2015-04-01

    Root reinforcement is recognized as an important factor for shallow landslides stability. Due to the complexity of root reinforcement mechanisms and the heterogeneity of the root-soil system, the estimation of parameters used in root reinforcement models is difficult, time consuming, and often highly uncertain. For practical applications, it is necessary to focus on the estimation of the most relevant parameters. The objective of the present contribution is to review the state of the art in the development of root reinforcement models and to discuss the sensitivity of the "Root Bundle Model" (RBM) when considering the variability of root mechanical properties and the heterogeneity of root distributions. The RBM is a strain-step loading fiber bundle model extended to include the mechanical and geometrical properties of roots. The model allows the calculation of the force-displacement behavior of a root bundle. In view of new results of field pullout tests performed on coarse roots of spruce (Picea abies) and considering a consistent dataset of root distribution of alpine tree species, we quantify the sensitivity of the RBM and the uncertainty associated with the most important input parameters. Preliminary results show that the extrapolation of force-diameter values from incomplete datasets (i.e., when only small roots are tested and values for coarse roots are extrapolated) may result in considerable errors. In particular, in the case of distributions with root diameters larger than 5 mm, root reinforcement tends to be dominated by coarse roots and their mechanical properties need to be quantified. In addition to the results of the model sensitivity, we present a possible best-practice method for the quantification of root reinforcement in view of its application to slope stability calculations and implementations in numerical models.

  18. Preoperative transcutaneous electrical nerve stimulation for localizing superficial nerve paths.

    PubMed

    Natori, Yuhei; Yoshizawa, Hidekazu; Mizuno, Hiroshi; Hayashi, Ayato

    2015-12-01

    During surgery, peripheral nerves are often seen to follow unpredictable paths because of previous surgeries and/or compression caused by a tumor. Iatrogenic nerve injury is a serious complication that must be avoided, and preoperative evaluation of nerve paths is important for preventing it. In this study, transcutaneous electrical nerve stimulation (TENS) was used for an in-depth analysis of peripheral nerve paths. This study included 27 patients who underwent the TENS procedure to evaluate the peripheral nerve path (17 males and 10 females; mean age: 59.9 years, range: 18-83 years) of each patient preoperatively. An electrode pen coupled to an electrical nerve stimulator was used for superficial nerve mapping. The TENS procedure was performed on patients' major peripheral nerves that passed close to the surgical field of tumor resection or trauma surgery, and intraoperative damage to those nerves was apprehensive. The paths of the target nerve were detected in most patients preoperatively. The nerve paths of 26 patients were precisely under the markings drawn preoperatively. The nerve path of one patient substantially differed from the preoperative markings with numbness at the surgical region. During surgery, the nerve paths could be accurately mapped preoperatively using the TENS procedure as confirmed by direct visualization of the nerve. This stimulation device is easy to use and offers highly accurate mapping of nerves for surgical planning without major complications. The authors conclude that TENS is a useful tool for noninvasive nerve localization and makes tumor resection a safe and smooth procedure. PMID:26420473

  19. Fluorescent sensors for organophosphorus nerve agent mimics.

    PubMed

    Dale, Trevor J; Rebek, Julius

    2006-04-12

    We present a small molecule sensor that provides an optical response to the presence of an organophosphorus (OP)-containing nerve agent mimic. The design contains three key features: a primary alcohol, a tertiary amine in close proximity to the alcohol, and a fluorescent group used as the optical readout. In the sensor's rest state, the lone pair of electrons of the basic amine quenches the fluorescence of the nearby fluorophore through photoinduced electron transfer (PET). Exposure to an OP nerve agent mimic triggers phosphorylation of the primary alcohol followed rapidly by an intramolecular substitution reaction as the amine displaces the created phosphate. The quaternized ammonium salt produced by this cyclization reaction no longer possesses a lone pair of electrons, and a fluorescence readout is observed as the nonradiative PET quenching pathway of the fluorophore is shut down. PMID:16594648

  20. Adapting to variable prismatic displacement

    NASA Technical Reports Server (NTRS)

    Welch, Robert B.; Cohen, Malcolm M.

    1989-01-01

    In each of two studies, subjects were exposed to a continuously changing prismatic displacement with a mean value of 19 prism diopters (variable displacement) and to a fixed 19-diopter displacement (fixed displacement). In Experiment 1, significant adaptation (post-pre shifts in hand-eye coordination) was found for fixed, but not for variable, displacement. Experiment 2 demonstrated that adaptation was obtained for variable displacement, but it was very fragile and is lost if the measures of adaptation are preceded by even a very brief exposure of the hand to normal or near-normal vision. Contrary to the results of some previous studies, an increase in within-S dispersion was not found of target pointing responses as a result of exposure to variable displacement.

  1. Chitosan crosslinked flat scaffolds for peripheral nerve regeneration.

    PubMed

    Fregnan, F; Ciglieri, E; Tos, P; Crosio, A; Ciardelli, G; Ruini, F; Tonda-Turo, C; Geuna, S; Raimondo, S

    2016-01-01

    Chitosan (CS) has been widely used in a variety of biomedical applications, including peripheral nerve repair, due to its excellent biocompatibility, biodegradability, readily availability and antibacterial activity. In this study, CS flat membranes, crosslinked with dibasic sodium phosphate (DSP) alone (CS/DSP) or in association with the γ-glycidoxypropyltrimethoxysilane (CS/GPTMS_DSP), were fabricated with a solvent casting technique. The constituent ratio of crosslinking agents and CS were previously selected to obtain a composite material having both adequate mechanical properties and high biocompatibility. In vitro cytotoxicity tests showed that both CS membranes allowed cell survival and proliferation. Moreover, CS/GPTMS_DSP membranes promoted cell adhesion, induced Schwann cell-like morphology and supported neurite outgrowth from dorsal root ganglia explants. Preliminary in vivo tests carried out on both types of nerve scaffolds (CS/DSP and CS/GPTMS_DSP membranes) demonstrated their potential for: (i) protecting, as a membrane, the site of nerve crush or repair by end-to-end surgery and avoiding post-operative nerve adhesion; (ii) bridging, as a conduit, the two nerve stumps after a severe peripheral nerve lesion with substance loss. A 1 cm gap on rat median nerve was repaired using CS/DSP and CS/GPTMS_DSP conduits to further investigate their ability to induce nerve regeneration in vivo. CS/GPTMS_DSP tubes resulted to be more fragile during suturing and, along a 12 week post-operative lapse of time, they detached from the distal nerve stump. On the contrary CS/DSP conduits promoted nerve fiber regeneration and functional recovery, leading to an outcome comparable to median nerve repaired by autograft. PMID:27508969

  2. Modeling root reinforcement using a root-failure Weibull survival function

    NASA Astrophysics Data System (ADS)

    Schwarz, M.; Giadrossich, F.; Cohen, D.

    2013-11-01

    Root networks contribute to slope stability through complex interactions with soil that include mechanical compression and tension. Due to the spatial heterogeneity of root distribution and the dynamics of root turnover, the quantification of root reinforcement on steep slopes is challenging and consequently the calculation of slope stability also. Although considerable progress has been made, some important aspects of root mechanics remain neglected. In this study we address specifically the role of root-strength variability on the mechanical behavior of a root bundle. Many factors contribute to the variability of root mechanical properties even within a single class of diameter. This work presents a new approach for quantifying root reinforcement that considers the variability of mechanical properties of each root diameter class. Using the data of laboratory tensile tests and field pullout tests, we calibrate the parameters of the Weibull survival function to implement the variability of root strength in a numerical model for the calculation of root reinforcement (RBMw). The results show that, for both laboratory and field data sets, the parameters of the Weibull distribution may be considered constant with the exponent equal to 2 and the normalized failure displacement equal to 1. Moreover, the results show that the variability of root strength in each root diameter class has a major influence on the behavior of a root bundle with important implications when considering different approaches in slope stability calculation. Sensitivity analysis shows that the calibration of the equations of the tensile force, the elasticity of the roots, and the root distribution are the most important steps. The new model allows the characterization of root reinforcement in terms of maximum pullout force, stiffness, and energy. Moreover, it simplifies the implementation of root reinforcement in slope stability models. The realistic quantification of root reinforcement for tensile

  3. Roots and Root Function: Introduction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A number of current issues related to water management, ecohydrology, and climate change are giving impetus to new research aimed at understanding roots and their functioning. Current areas of research include: use of advanced imaging technologies such as Magnetic Resonance Imaging to observe roots...

  4. Cauda equina repair in the rat: part 1. Stimulus-evoked EMG for identifying spinal nerves innervating intrinsic tail muscles.

    PubMed

    Blaskiewicz, Don J; Smirnov, Igor; Cisu, Tudor; DeRuisseau, Lara R; Stelzner, Dennis J; Calancie, Blair

    2009-08-01

    Cauda equina injuries may produce severe leg and pelvic floor dysfunction, for which no effective treatments exist. We are developing a rat cauda equina injury model to allow nerve root identification and surgical repair. One possible difficulty in implementing any repair strategy after trauma in humans involves the correct identification of proximal and distal ends of nerve roots separated by the injury. Two series of studies were carried out. In Series 1, we electrically stimulated segmental contributors to the dorsal and ventral caudales nerves in order to characterize the recruitment patterns of muscles controlling rat tail movements. In Series 2, we attempted to identify individual nerve roots forming the cauda equina by both level of origin and function (i.e., dorsal or ventral), based solely upon the recruitment patterns in response to electrical stimulation. For Series 1 studies, electrical stimulation of the segmental contributors showed that all nerve roots-from the sixth lumbar to the first coccygeal-contributed to recruitment of muscles found at the base of the tail. Intrinsic tail muscles lying more distally in the tail showed a more root-specific pattern of innervation. For Series 2, the rate of successful identification of an unknown nerve root as being ventral was very high (>95%), and only somewhat lower (approximately 80%) for dorsal roots. Correctly identifying the level of origin of that root was more difficult, but for ventral roots this rate still exceeded 90%. Using the rat cauda equina model, we have shown that stimulus-evoked EMG can be used to identify ventral nerve roots innervating tail muscles with a high degree of accuracy. These findings support the feasibility of using this conceptual approach for identifying and repairing damaged human cauda equina nerve roots based on stimulus-evoked recruitment of muscles in the leg and pelvic floor. PMID:19203211

  5. Variable displacement blower

    DOEpatents

    Bookout, Charles C.; Stotts, Robert E.; Waring, Douglass R.; Folsom, Lawrence R.

    1986-01-01

    A blower having a stationary casing for rotatably supporting a rotor assembly having a series of open ended chambers arranged to close against the surrounding walls of the casing. Pistons are slidably mounted within each chamber with the center of rotation of the pistons being offset in regard to the center of rotation of the rotor assembly whereby the pistons reciprocate in the chambers as the rotor assembly turns. As inlet port communicates with the rotor assembly to deliver a working substance into the chamber as the pistons approach a top dead center position in the chamber while an outlet port also communicates with the rotor to exhaust the working substance as the pistons approach a bottom dead center position. The displacement of the blower is varied by adjusting the amount of eccentricity between the center of rotation of the pistons and the center of rotation of the rotor assembly.

  6. Strategies for displacing oil

    NASA Astrophysics Data System (ADS)

    Rao, Vikram; Gupta, Raghubir

    2015-03-01

    Oil currently holds a monopoly on transportation fuels. Until recently biofuels were seen as the means to break this stranglehold. They will still have a part to play, but the lead role has been handed to natural gas, almost solely due to the increased availability of shale gas. The spread between oil and gas prices, unprecedented in its scale and duration, will cause a secular shift away from oil as a raw material. In the transport fuel sector, natural gas will gain traction first in the displacement of diesel fuel. Substantial innovation is occurring in the methods of producing liquid fuel from shale gas at the well site, in particular in the development of small scale distributed processes. In some cases, the financing of such small-scale plants may require new business models.

  7. Injuries to the spinal accessory nerve: a lesson to surgeons.

    PubMed

    Camp, S J; Birch, R

    2011-01-01

    The integrity of the spinal accessory nerve is fundamental to thoracoscapular function and essential for scapulohumeral rhythm. This nerve is vulnerable along its superficial course. This study assessed the delay in diagnosis and referral for management of damage to this nerve, clarified its anatomical course and function, and documented the results of repair. From examination of our records, 111 patients with lesions of the spinal accessory nerve were treated between 1984 and 2007. In 89 patients (80.2%) the damage was iatropathic. Recognition and referral were seldom made by the surgeon responsible for the injury, leading to a marked delay in instituting treatment. Most referrals were made for painful loss of shoulder function. The clinical diagnosis is straightforward. There is a characteristic downward and lateral displacement of the scapula, with narrowing of the inferior scapulohumeral angle and loss of function, with pain commonly present. In all, 80 nerves were explored and 65 were repaired. The course of the spinal accessory nerve in relation to the sternocleidomastoid muscle was constant, with branches from the cervical plexus rarely conveying motor fibres. Damage to the nerve was predominantly posterior to this muscle. Despite the delay, the results of repair were surprising, with early relief of pain, implying a neuropathic source, which preceded generally good recovery of muscle function. PMID:21196545

  8. Radial Nerve Tendon Transfers.

    PubMed

    Cheah, Andre Eu-Jin; Etcheson, Jennifer; Yao, Jeffrey

    2016-08-01

    Radial nerve palsy typically occurs as a result of trauma or iatrogenic injury and leads to the loss of wrist extension, finger extension, thumb extension, and a reduction in grip strength. In the absence of nerve recovery, reconstruction of motor function involves tendon transfer surgery. The most common donor tendons include the pronator teres, wrist flexors, and finger flexors. The type of tendon transfer is classified based on the donor for the extensor digitorum communis. Good outcomes have been reported for most methods of radial nerve tendon transfers as is typical for positional tendon transfers not requiring significant power. PMID:27387076

  9. Displacement Parameter Inversion for a Novel Electromagnetic Underground Displacement Sensor

    PubMed Central

    Shentu, Nanying; Li, Qing; Li, Xiong; Tong, Renyuan; Shentu, Nankai; Jiang, Guoqing; Qiu, Guohua

    2014-01-01

    Underground displacement monitoring is an effective method to explore deep into rock and soil masses for execution of subsurface displacement measurements. It is not only an important means of geological hazards prediction and forecasting, but also a forefront, hot and sophisticated subject in current geological disaster monitoring. In previous research, the authors had designed a novel electromagnetic underground horizontal displacement sensor (called the H-type sensor) by combining basic electromagnetic induction principles with modern sensing techniques and established a mutual voltage measurement theoretical model called the Equation-based Equivalent Loop Approach (EELA). Based on that work, this paper presents an underground displacement inversion approach named “EELA forward modeling-approximate inversion method”. Combining the EELA forward simulation approach with the approximate optimization inversion theory, it can deduce the underground horizontal displacement through parameter inversion of the H-type sensor. Comprehensive and comparative studies have been conducted between the experimentally measured and theoretically inversed values of horizontal displacement under counterpart conditions. The results show when the measured horizontal displacements are in the 0–100 mm range, the horizontal displacement inversion discrepancy is generally tested to be less than 3 mm under varied tilt angles and initial axial distances conditions, which indicates that our proposed parameter inversion method can predict underground horizontal displacement measurements effectively and robustly for the H-type sensor and the technique is applicable for practical geo-engineering applications. PMID:24858960

  10. Displacement parameter inversion for a novel electromagnetic underground displacement sensor.

    PubMed

    Shentu, Nanying; Li, Qing; Li, Xiong; Tong, Renyuan; Shentu, Nankai; Jiang, Guoqing; Qiu, Guohua

    2014-01-01

    Underground displacement monitoring is an effective method to explore deep into rock and soil masses for execution of subsurface displacement measurements. It is not only an important means of geological hazards prediction and forecasting, but also a forefront, hot and sophisticated subject in current geological disaster monitoring. In previous research, the authors had designed a novel electromagnetic underground horizontal displacement sensor (called the H-type sensor) by combining basic electromagnetic induction principles with modern sensing techniques and established a mutual voltage measurement theoretical model called the Equation-based Equivalent Loop Approach (EELA). Based on that work, this paper presents an underground displacement inversion approach named "EELA forward modeling-approximate inversion method". Combining the EELA forward simulation approach with the approximate optimization inversion theory, it can deduce the underground horizontal displacement through parameter inversion of the H-type sensor. Comprehensive and comparative studies have been conducted between the experimentally measured and theoretically inversed values of horizontal displacement under counterpart conditions. The results show when the measured horizontal displacements are in the 0-100 mm range, the horizontal displacement inversion discrepancy is generally tested to be less than 3 mm under varied tilt angles and initial axial distances conditions, which indicates that our proposed parameter inversion method can predict underground horizontal displacement measurements effectively and robustly for the H-type sensor and the technique is applicable for practical geo-engineering applications. PMID:24858960

  11. Selective vulnerability of peripheral nerves in avian riboflavin deficiency demyelinating polyneuropathy.

    PubMed

    Cai, Z; Blumbergs, P C; Finnie, J W; Manavis, J; Thompson, P D

    2009-01-01

    Riboflavin (vitamin B2) deficiency in young chickens produces a demyelinating peripheral neuropathy. In this study, day-old broiler meat chickens were fed a riboflavin-deficient diet (1.8 mg/kg) and killed on posthatch days 6, 11, 16, 21, and 31, while control chickens were given a conventional diet containing 5.0 mg/kg riboflavin. Pathologic changes were found in sciatic, cervical, and lumbar spinal nerves of riboflavin-deficient chickens from day 11 onwards, characterized by endoneurial oedema, hypertrophic Schwann cells, tomacula (redundant myelin swellings), demyelination/remyelination, lipid deposition, and fibroblastic onion bulb formation. Similar changes were also found in large and medium intramuscular nerves, although they were less severe in the latter. However, by contrast, ventral and dorsal spinal nerve roots, distal intramuscular nerves, and subcutaneous nerves were normal at all time points examined. These findings demonstrate, for the first time, that riboflavin deficiency in young, rapidly growing chickens produces selective injury to peripheral nerve trunks, with relative sparing of spinal nerve roots and distal nerve branches to muscle and skin. These novel findings suggest that the response of Schwann cells in peripheral nerves with riboflavin deficiency differs because either there are subsets of these cells in, or there is variability in access of nutrients to, different sites within the nerves. PMID:19112122

  12. Measuring vulnerability to disaster displacement

    NASA Astrophysics Data System (ADS)

    Brink, Susan A.; Khazai, Bijan; Power, Christopher; Wenzel, Friedemann

    2015-04-01

    Large scale disasters can cause devastating impacts in terms of population displacement. Between 2008 and 2013, on average 27 million people were displaced annually by disasters (Yonetani 2014). After large events such as hurricane Katrina or the Port-au-Prince earthquake, images of inadequate public shelter and concerns about large scale and often inequitable migration have been broadcast around the world. Population displacement can often be one of the most devastating and visible impacts of a natural disaster. Despite the importance of population displacement in disaster events, measures to understand the socio-economic vulnerability of a community often use broad metrics to estimate the total socio-economic risk of an event rather than focusing on the specific impacts that a community faces in a disaster. Population displacement is complex and multi-causal with the physical impact of a disaster interacting with vulnerability arising from the response, environmental issues (e.g., weather), cultural concerns (e.g., expectations of adequate shelter), and many individual factors (e.g., mobility, risk perception). In addition to the complexity of the causes, population displacement is difficult to measure because of the wide variety of different terms and definitions and its multi-dimensional nature. When we speak of severe population displacement, we may refer to a large number of displaced people, an extended length of displacement or associated difficulties such as poor shelter quality, risk of violence and crime in shelter communities, discrimination in aid, a lack of access to employment or other difficulties that can be associated with large scale population displacement. We have completed a thorough review of the literature on disaster population displacement. Research has been conducted on historic events to understand the types of negative impacts associated with population displacement and also the vulnerability of different groups to these impacts. We

  13. High Ulnar Nerve Injuries: Nerve Transfers to Restore Function.

    PubMed

    Patterson, Jennifer Megan M

    2016-05-01

    Peripheral nerve injuries are challenging problems. Nerve transfers are one of many options available to surgeons caring for these patients, although they do not replace tendon transfers, nerve graft, or primary repair in all patients. Distal nerve transfers for the treatment of high ulnar nerve injuries allow for a shorter reinnervation period and improved ulnar intrinsic recovery, which are critical to function of the hand. PMID:27094893

  14. Mandibular nerve paresthesia caused by endodontic treatment.

    PubMed

    Gallas-Torreira, M Mercedes; Reboiras-López, M Dolores; García-García, Abel; Gándara-Rey, José

    2003-01-01

    The paresthesias of the inferior dental nerve consists of a complication that can occur after performing various dental procedures such as cystectomies, extraction of impacted teeth, apicoectomies, endodontic treatments, local anesthetic deposition, preprosthetic or implantologic surgery. The possible mechanisms of nervous lesions are mechanical, chemical and thermal. Mechanical injury includes compression, stretching, partial or total resection and laceration. The lesion can cause a discontinuity to the nerve with Wallerian degeneration of the distal and integrated fibers of the covering (axonotmesis) or can cause the total sectioning of the nerve (neurotmesis). Chemical trauma can be due to certain toxic components of the endodontic filling materials (paraformaldehyde, corticoids or eugenol) and irrigating solutions (sodium hypochlorite) or local anesthetics. Thermal injury is a consequence of bone overheating during the execution of surgical techniques. We present a clinical case of paresthesia of the inferior dental nerve after the introduction of a gutta-percha point in the mandibular canal during the performance of a root canal therapy of the inferior first molar. The etiology and the treatment of this endodontic complication are described. PMID:12937392

  15. Assessment of Median Nerve Mobility by Ultrasound Dynamic Imaging for Diagnosing Carpal Tunnel Syndrome.

    PubMed

    Kuo, Tai-Tzung; Lee, Ming-Ru; Liao, Yin-Yin; Chen, Jiann-Perng; Hsu, Yen-Wei; Yeh, Chih-Kuang

    2016-01-01

    Carpal tunnel syndrome (CTS) is the most common peripheral neuropathy and is characterized by median nerve entrapment at the wrist and the resulting median nerve dysfunction. CTS is diagnosed clinically as the gold standard and confirmed with nerve conduction studies (NCS). Complementing NCS, ultrasound imaging could provide additional anatomical information on pathological and motion changes of the median nerve. The purpose of this study was to estimate the transverse sliding patterns of the median nerve during finger movements by analyzing ultrasound dynamic images to distinguish between normal subjects and CTS patients. Transverse ultrasound images were acquired, and a speckle-tracking algorithm was used to determine the lateral displacements of the median nerve in radial-ulnar plane in B-mode images utilizing the multilevel block-sum pyramid algorithm and averaging. All of the averaged lateral displacements at separate acquisition times within a single flexion-extension cycle were accumulated to obtain the cumulative lateral displacements, which were curve-fitted with a second-order polynomial function. The fitted curve was regarded as the transverse sliding pattern of the median nerve. The R2 value, curvature, and amplitude of the fitted curves were computed to evaluate the goodness, variation and maximum value of the fit, respectively. Box plots, the receiver operating characteristic (ROC) curve, and a fuzzy c-means clustering algorithm were utilized for statistical analysis. The transverse sliding of the median nerve during finger movements was greater and had a steeper fitted curve in the normal subjects than in the patients with mild or severe CTS. The temporal changes in transverse sliding of the median nerve within the carpal tunnel were found to be correlated with the presence of CTS and its severity. The representative transverse sliding patterns of the median nerve during finger movements were demonstrated to be useful for quantitatively estimating

  16. Assessment of Median Nerve Mobility by Ultrasound Dynamic Imaging for Diagnosing Carpal Tunnel Syndrome

    PubMed Central

    Kuo, Tai-Tzung; Lee, Ming-Ru; Liao, Yin-Yin; Chen, Jiann-Perng; Hsu, Yen-Wei; Yeh, Chih-Kuang

    2016-01-01

    Carpal tunnel syndrome (CTS) is the most common peripheral neuropathy and is characterized by median nerve entrapment at the wrist and the resulting median nerve dysfunction. CTS is diagnosed clinically as the gold standard and confirmed with nerve conduction studies (NCS). Complementing NCS, ultrasound imaging could provide additional anatomical information on pathological and motion changes of the median nerve. The purpose of this study was to estimate the transverse sliding patterns of the median nerve during finger movements by analyzing ultrasound dynamic images to distinguish between normal subjects and CTS patients. Transverse ultrasound images were acquired, and a speckle-tracking algorithm was used to determine the lateral displacements of the median nerve in radial-ulnar plane in B-mode images utilizing the multilevel block-sum pyramid algorithm and averaging. All of the averaged lateral displacements at separate acquisition times within a single flexion–extension cycle were accumulated to obtain the cumulative lateral displacements, which were curve-fitted with a second-order polynomial function. The fitted curve was regarded as the transverse sliding pattern of the median nerve. The R2 value, curvature, and amplitude of the fitted curves were computed to evaluate the goodness, variation and maximum value of the fit, respectively. Box plots, the receiver operating characteristic (ROC) curve, and a fuzzy c-means clustering algorithm were utilized for statistical analysis. The transverse sliding of the median nerve during finger movements was greater and had a steeper fitted curve in the normal subjects than in the patients with mild or severe CTS. The temporal changes in transverse sliding of the median nerve within the carpal tunnel were found to be correlated with the presence of CTS and its severity. The representative transverse sliding patterns of the median nerve during finger movements were demonstrated to be useful for quantitatively estimating

  17. A novel chondroitin sulfate hydrogel for nerve repair

    NASA Astrophysics Data System (ADS)

    Conovaloff, Aaron William

    Brachial plexus injuries affect numerous patients every year, with very debilitating results. The majority of these cases are very severe, and involve damage to the nerve roots. To date, repair strategies for these injuries address only gross tissue damage, but do not supply cells with adequate regeneration signals. As a result, functional recovery is often severely lacking. Therefore, a chondroitin sulfate hydrogel that delivers neurotrophic signals to damaged neurons is proposed as a scaffold to support nerve root regeneration. Capillary electrophoresis studies revealed that chondroitin sulfate can physically bind with a variety of neurotrophic factors, and cultures of chick dorsal root ganglia demonstrated robust neurite outgrowth in chondroitin sulfate hydrogels. Outgrowth in chondroitin sulfate gels was greater than that observed in control gels of hyaluronic acid. Furthermore, the chondroitin sulfate hydrogel's binding activity with nerve growth factor could be enhanced by incorporation of a synthetic bioactive peptide, as revealed by fluorescence recovery after photobleaching. This enhanced binding was observed only in chondroitin sulfate gels, and not in hyaluronic acid control gels. This enhanced binding activity resulted in enhanced dorsal root ganglion neurite outgrowth in chondroitin sulfate gels. Finally, the growth of regenerating dorsal root ganglia in these gels was imaged using label-free coherent anti-Stokes scattering microscopy. This technique generated detailed, high-quality images of live dorsal root ganglion neurites, which were comparable to fixed, F-actin-stained samples. Taken together, these results demonstrate the viability of this chondroitin sulfate hydrogel to serve as an effective implantable scaffold to aid in nerve root regeneration.

  18. Nerve Growth Factor Decreases in Sympathetic and Sensory Nerves of Rats with Chronic Heart Failure

    PubMed Central

    Lu, Jian

    2014-01-01

    Nerve growth factor (NGF) plays a critical role in the maintenance and survival of both sympathetic and sensory nerves. Also, NGF can regulate receptor expression and neuronal activity in the sympathetic and sensory neurons. Abnormalities in NGF regulation are observed in patients and animals with heart failure (HF). Nevertheless, the effects of chronic HF on the levels of NGF within the sympathetic and sensory nerves are not known. Thus, the ELISA method was used to assess the levels of NGF in the stellate ganglion (SG) and dorsal root ganglion (DRG) neurons of control rats and rats with chronic HF induced by myocardial infarction. Our data show for the first time that the levels of NGF were significantly decreased (P < 0.05) in the SG and DRG neurons 6–20 weeks after ligation of the coronary artery. In addition, a close relation was observed between the NGF levels and the left ventricular function. In conclusion, chronic HF impairs the expression of NGF in the sympathetic and sensory nerves. Given that sensory afferent nerves are engaged in the sympathetic nervous responses to somatic stimulation (i.e. muscle activity during exercise) via a reflex mechanism, our data indicate that NGF is likely responsible for the development of muscle reflex-mediated abnormal sympathetic responsiveness observed in chronic HF. PMID:24913185

  19. Degenerative Nerve Diseases

    MedlinePlus

    Degenerative nerve diseases affect many of your body's activities, such as balance, movement, talking, breathing, and heart function. Many of these diseases are genetic. Sometimes the cause is a medical ...

  20. Common peroneal nerve dysfunction

    MedlinePlus

    ... people: Who are very thin (for example, from anorexia nervosa ) Who have certain autoimmune conditions, such as ... Elsevier; 2013:chap 22. Read More Alertness - decreased Anorexia Broken bone Diabetes and nerve damage Mononeuritis multiplex ...

  1. Ulnar nerve dysfunction

    MedlinePlus

    ... pressure on the elbow An elbow fracture or dislocation Temporary pain and tingling of this nerve can ... Saunders; 2011:chap 428. Read More Broken bone Dislocation Mononeuritis multiplex Mononeuropathy Myelin Peripheral neuropathy Systemic Update ...

  2. Diabetic Nerve Problems

    MedlinePlus

    ... at the wrong times. This damage is called diabetic neuropathy. Over half of people with diabetes get ... you change positions quickly Your doctor will diagnose diabetic neuropathy with a physical exam and nerve tests. ...

  3. Ulnar nerve dysfunction

    MedlinePlus

    ... surface of the body where it crosses the elbow. The damage destroys the nerve covering ( myelin sheath) ... be caused by: Long-term pressure on the elbow An elbow fracture or dislocation Temporary pain and ...

  4. Femoral nerve dysfunction

    MedlinePlus

    Neuropathy - femoral nerve; Femoral neuropathy ... Craig EJ, Clinchot DM. Femoral neuropathy. In: Frontera WR, Silver JK, Rizzo TD Jr, eds. Essentials of Physical Medicine and Rehabilitation: Musculoskeletal Disorders, Pain, and Rehabilitation . 3rd ...

  5. Diabetic Nerve Problems

    MedlinePlus

    ... the wrong times. This damage is called diabetic neuropathy. Over half of people with diabetes get it. ... change positions quickly Your doctor will diagnose diabetic neuropathy with a physical exam and nerve tests. Controlling ...

  6. Femoral nerve dysfunction

    MedlinePlus

    ... An abnormal knee reflex Smaller than normal quadriceps muscles on the front of the thigh Tests that may be done include: Electromyography ( EMG ) Nerve conduction tests ( NCV ), usually done at ...

  7. Schwannoma of Extraocular Nerves

    PubMed Central

    Niazi, Wasim; Boggan, James E.

    1994-01-01

    An unusual case of schwannoma arising from the third cranial nerve in a thirteen year old male is reported. The patient presented with paresis of the right oculomotor nerve and ipsilateral hemiparesis. The clinical features of this case are discussed and the pertinent medical literature reviewed. ImagesFigure 1p220-bFigure 2Figure 3Figure 4Figure 5Figure 6 PMID:17171175

  8. How minimum detectable displacement in a GNSS Monitoring Network change?

    NASA Astrophysics Data System (ADS)

    Hilmi Erkoç, Muharrem; Doǧan, Uǧur; Aydın, Cüneyt

    2016-04-01

    The minimum detectable displacement in a geodetic monitoring network shows the displacement magnitude which may be just discriminated with known error probabilities. This displacement, which is originally deduced from sensitivity analysis, depends on network design, observation accuracy, datum of the network, direction of the displacement and power of the statistical test used for detecting the displacements. One may investigate how different scenarios on network design and observation accuracies influence the minimum detectable displacements for the specified datum, a-priorly forecasted directions and assumed power of the test and decide which scenario is the best or most optimum. It is sometimes difficult to forecast directions of the displacements. In that case, the minimum detectable displacements in a geodetic monitoring network are derived on the eigen-directions associated with the maximum eigen-values of the network stations. This study investigates how minimum detectable displacements in a GNSS monitoring network change depending on the accuracies of the network stations. For this, CORS-TR network in Turkey with 15 stations (a station fixed) is used. The data with 4h, 6h, 12 h and 24 h observing session duration in three sequential days of 2011, 2012 and 2013 were analyzed with Bernese 5.2 GNSS software. The repeatabilities of the daily solutions belonging to each year were analyzed carefully to scale the Bernese cofactor matrices properly. The root mean square (RMS) values for daily repeatability with respect to the combined 3-day solution are computed (the RMS values are generally less than 2 mm in the horizontal directions (north and east) and < 5 mm in the vertical direction for 24 h observing session duration). With the obtained cofactor matrices for these observing sessions, the minimum detectable displacements along the (maximum) eigen directions are compared each other. According to these comparisons, more session duration less minimum detectable

  9. Sural nerve defects after nerve biopsy or nerve transfer as a sensory regeneration model for peripheral nerve conduit implantation.

    PubMed

    Radtke, C; Kocsis, J D; Reimers, K; Allmeling, C; Vogt, P M

    2013-09-01

    Nerve repair after injury can be effectively accomplished by direct suture approximation of the proximal and distal segments. This is more successful if coadaptation can be achieved without tension. Currently, the gold standard repair of larger deficits is the transplantation of an autologous sensory sural nerve graft. However, a significant disadvantage of this technique is the inevitable donor morbidity (sensory loss, neuroma and scar formation) after harvesting of the sural nerve. Moreover, limitation of autologous donor nerve length and fixed diameter of the available sural nerve are major drawbacks of current autograft treatment. Another approach that was introduced for nerve repair is the implantation of alloplastic nerve tubes made of, for example, poly-L-lactide. In these, nerve stumps of the transected nerves are surgically bridged using the biosynthetic conduit. A number of experimental studies, primarily in rodents, indicate axonal regeneration and remyelination after implantation of various conduits. However, only limited clinical studies with conduit implantation have been performed in acute peripheral nerve injuries particularly on digital nerves. Clinical transfer of animal studies, which can be carefully calibrated for site and extent of injury, to humans is difficult to interpret due to the intrinsic variability in human nerve injuries. This prevents effective quantification of improvement and induces bias in the study. Therefore, standardization of lesion/repair in human studies is warranted. Here we propose to use sural nerve defects, induced due to nerve graft harvesting or from diagnostic nerve biopsies as a model site to enable standardization of nerve conduit implantation. This would help better with the characterization of the implants and its effectiveness in axonal regeneration and remyelination. Nerve regeneration can be assessed, for example, by recovery of sensation, measured non-invasively by threshold to von Frey filaments and cold

  10. Patient-specific factors in the proximity of the inferior alveolar nerve to the tooth apex

    PubMed Central

    Adigüzel, Özkan; Kaya, Sadullah; Akkuş, Zeki

    2012-01-01

    Objectives: To evaluate whether age and gender differences are predictive factors for inferior alveolar nerve position with respect to mandibular first molar roots. Study Design: Cone-beam computed tomography scans [0.2-mm3 voxel size; n = 200 (100 males, 100 females)] of patients aged 15–65 years showing mandibular first and second molars were included in this study. Patients with pathoses that might affect inferior alveolar nerve position, including second molar and/or first premolar extraction, were excluded. Fourteen measurements (mm) were taken from the inferior alveolar nerve to the mesial and distal root apices. Subjects were grouped by age and gender. Data were analysed using two-way analyses of variance with post hoc Bonferroni corrections. Results: The distance from the inferior alveolar nerve to the root apices was smaller in females than males, regardless of age (p < 0.01). Distal roots were closer to the nerve than mesial roots in both genders (p < 0.05). Total buccolingual mandibular length (at 3-mm apical level) was shorter in females than males (p < 0.01) but mean buccolingual mandibular width at the level of the inferior alveolar canal did not differ. Nerve–root apex distances were significantly shorter in males and females aged 16–25 and 56–65 years than in other age groups (p < 0.01). Conclusions: The distance between inferior alveolar nerve and mandibular first molar roots depends upon the age and gender: it is shorter in females than in males and in subjects aged 16–25 years and >55 years than in other age groups. Key words:Age, cone-beam computed tomography, inferior alveolar nerve, root apex, gender. PMID:22926478